FAQ on Directed Panspermia, Sections ABCD

[pnyikos]

I am starting a new thread for my FAQ on directed panspermia, but will
also be tying up some loose ends on the first thread that I devoted to
this topic late last autumn. Today I will be posting a slightly
revised Section A and a slightly longer Section B. Then tomorrow, I
will post my first draft for Section C, and I hope also to post a
first draft for Section D this week. Here are what these sections are
about:

A. Origins of the Theory of Directed Panspermia

B. Some Pointed Questions about Directed Panspermia

C: Connections with abiogenesis and intelligent design

D. Delivery Systems

There is at least one more section in the planning stages, but I'd be
starting a new thread for those.

Peter Nyikos
Professor, Dept. of Mathematics -- standard disclaimer--
University of South Carolina
http://www.math.sc.edu/~nyikos/
nyikos @ math.sc.edu

[pnyikos]

A. Origins of the Theory of Directed Panspermia

A1. What is directed panspermia?

It is the theory that was introduced by Nobel Laureate biochemist
Francis Crick and another distinguished biochemist, Leslie Orgel. As
they put it, it is

"the theory that organisms were deliberately
transmitted to the earth by intelligent beings
on another planet."
-- Icarus 19 (1973) 341-346
http://profiles.nlm.nih.gov/ps/access/SCBCCP.pdf

All quotes from them below are taken from this same source. Another
website with the same article in more easily readable form [though
containing some typos] can be found here:

http://www.checktheevidence.com/Disclosure/PDF%20Documents/Directed%20Panspermia%20F.%20H.%20C.%20CRICK%20AND%20L.%20E.%20Orgel.pdf



A2. How does directed panspermia relate to the "spore theory" of
Arrhenius and the "comet theory" of Hoyle and Wickramasinghe?

These theories, which predate the theory of directed panspermia, also
come under the heading of "panspermia." However, they are like
directed panspermia only insofar as they hypothesize that life as we
know it on earth began elsewhere. That is, microorganisms reached
earth from elsewhere and evolved into all other forms of earth life.
But unlike Crick and Orgel, these scientists did not assume any
intelligent agents had anything to do with the "transmission."


A3. What kinds of organisms and what means of transmission did Crick
and Orgel hypothesize?

"Could life have started on Earth as a
result of infection by microorganisms
sent here deliberately by a technological
society on another planet, by means
of a special long range unmanned spaceship?"

A little later in the article, they get very specific, but only for
illustrative purposes; their general theory is as above.

"The spaceship would carry large samples
of a number of microorganisms,
each having different but simple
nutritional requirements, for example
bluegreen algae, which could grow
on CO2, and water in `sunlight.
A payload of 1000kg might be made up
of 10 samples each containing 10^16
microorganisms, or 100 samples each of
10^15 microorganisms.



A4. Didn't Crick and Orgel consider the sending of organisms other
than microorganisms?

Yes, but only to comparatively nearby planetary systems. As Crick
later put it several times in _Life Itself_, "prokaryotes travel
farther". He and Orgel put it this way:

"It may be possible in the future to
send either mice or men or elaborate
instruments to the planets of other
Solar Systems (as so often described
in science fiction) but a rocket
carrying microorganisms will always
have a much greater effective range
and so be advantageous if the sole aim
is to spread life."

They go on to give several reasons immediately afterwards.



A5. What kinds of "unmanned spaceships" did Crick and Orgel have in
mind?

Very slow ones, considering the vast distances between planetary
systems.

"It would not be necessary to accelerate
the spaceship to extremely high velocities,
since its time of arrival would not be important.
The radius of our galaxy is about 10^5 light years,
so we could infect most planets in the galaxy
within 10^8 yr by means of a spaceship travelling
at only onethousandths of the velocity of light.
Several thousand stars are within a hundred light
years of the Earth and could be reached within as
little as a million years by a spaceship travelling
at 60,000 mph, or within 10,000 yr if a speed
one-hundredth of that of light were possible."

Unbeknownst to Crick and Orgel, in the same year this appeared, a
think tank of the British Interplanetary Society went to work
designing a spaceship almost within reach of our technology, capable
of speeds of about one-tenth of the speed of light. More about this,
and another such project within our technological abilities right now,
will appear in a later section of this FAQ.


A6. How did Crick and Orgel imagine that microorganisms could stay
alive that long?

"The question of how long microorganisms,
and in particular bacterial spores,
could survive in a spaceship
has been considered in a preliminary way
by Sneath (1962). He concludes
`that life could probably be preserved
for periods of more than a million years
if suitably protected and maintained
at temperatures close to absolute zero.'
Sagan (1960) has given a comparable estimate
of the effects of radiation damage."



A7. What evidence did Crick and Orgel give for the theory of directed
panspermia?

The the scientific evidence was indirect, and admittedly weak. It took
two forms. One was the near-universality of the genetic code. [There
is one variation in ciliates and a few others in various mitochondria,
but the differences are very minor and point to a common ancestral
source.]

It is a little surprising that organisms
with somewhat different codes do not coexist.
The universality of the code follows
naturally from infective theory
of the origins of life. Life on earth
would represent a clone derived
from a single extraterrestrial organism.
Even if many codes were represented at
the primary site where life began, only a
single one might have operated in
the organisms used to infect the Earth.

Of course, they acknowledged that there were various theories for the
near-universality of the code, "but none is generally accepted to be
completely convincing." [ibid.] Here is their other piece of strictly
scientific evidence:

Molybdenum is an essential trace element
that plays an important role in many
enzymatic reactions, while chromium
and nickel are relatively unimportant
in biochemistry. The abundance of chromium,
nickel, and molybdenum on the Earth are 0.20,
3.16, and 0.02%, respectively. We cannot
conclude anything from this single example,
since molybdenum may be irreplaceable in
some essential reaction -- nitrogen fixation,
for example. However, if it could be shown
that the elements represented in terrestrial
living organisms correlate closely with those
that are abundant in some class of star ... we
might look more sympathetically at "infective�
theories.

They also had some reasoning that belongs more to the philosophy of
science than to science *per se*. They make reference to "the theorem
of detailed cosmic
reversibility" and apply it thus, near the beginning of the article:

If we are capable of infecting an
*as yet* lifeless extrasolar planet,
then, given that the time was available,
another technological society might
well have infected our planet when
it was still lifeless.

They go on later in the article to speculate on various motives the
panspermists might have had. The one that most dovetails with "the
theorem" is this:

It seems unlikely that we would deliberately
send terrestrial organisms to planets
that we believed might already be inhabited.
However, in view of the precarious situation
on Earth, we might well be tempted to infect
other planets if we became convinced that
we were alone in the galaxy (Universe).
...
The hypothetical senders on another planet
may have been able to prove that they were
likely to be alone, and to remain so, or they
may have reached this conclusion mistakenly.
In either case, if they resembled us
psychologically, their motivation for polluting
the galaxy would be strong, if they believed
that all or even the great majority of
inhabitable planets could be given life by
Directed Panspermia.

NEXT: B. Some Pointed Questions about Directed Panspermia

[pnyikos]

B8 was introduced after the original Section B FAQ post, and B9
appears here for the first time. Also, B2 is slightly revised in the
light of some experiments reported on by Shapiro.

B. Some Pointed Questions about Directed Panspermia

B1. Doesn't directed panspermia simply "kick the can down the road"
where the origin of life is concerned?

This question is based on a misconception of what the directed
panspermia hypothesis is all about. It has nothing to say about the
ultimate origins of life in our universe; it is about the origin of
life ON EARTH.

B2. Aren't origin-of-life experiments showing that life very likely
began on earth?

The experiments have yet to produce even one of the four basic
nucleotides of RNA under simulation of conditions on the early earth,
after over six decades since the original Urey-Miller experiment. In
fact one website that has been approvingly quoted by "evolutionists"
in talk.origins has gone so far to say that scientists aren't trying
to produce life from scratch in the laboratory, at all.

The experiments that have been done to date only help to shed light
(very feeble light at that, see B7 below) as to how abiogenesis could
take place *somewhere*.

B3. But doesn't Ockham's Razor strongly favor life abiotically
produced on earth rather than by seeding by space aliens?

Ockham's Razor decrees only that the most parsimonious explanation be
given after ALL evidence has been scrutinized, and what little
evidence there is [see the answer to A7], is on the side of directed
panspermia.

By the way, the wording "space aliens" is a bit misleading in that it
suggests that the panspermists engaged in far-ranging space travel,
whereas they might never have even gone as far as the last large
planet in their system. The distances between stars are so great,
that all probes to other systems might have been only carrying much
smaller and hardier organisms than the intelligent species to which
the panspermists belonged.

B4. Why have we not found any evidence of space probes? Doesn't that
count as evidence against directed panspermia?

[The following answer is taken largely
from http://groups.google.com/group/talk.origins/msg/a984ba163776071f]

This question begs the question. What artifact could possibly have
survived meteor bombardments on the moon or other body, or plate
tectonics and weathering on earth, over close to 4 billion years? What
evidence at all? The best answer takes us far away from the concept of
a probe: a biological organism, able to propagate its characteristics
indefinitely.

For instance, the panspermists might have invented the highly unusual
device called the bacterial flagellum, which is useful enough to have
a good chance of staying in existence all those billions of years
through being handed down from one generation to the next.

I once suggested that it may partly have been designed as a sort of
analogue of "Kilroy was here": intelligent beings eventually evolving
from the microscopic life the panspermists sent might look at it and
begin to suspect that their existence is due to another species having
sent life to earth, and be suitably appreciative of the gift of life
to the unknown beings that sent it.

B5. What about the astronomical expenses of a panspermia project?

The expenses would be spread out over thousands, perhaps millions of
years in the sort of project that Crick and Orgel had in mind. The
project might grow out of a long project of simply exploring the
planets of other stars with instrumental probes, and during that time
the panspermists could be expected to mine a great many asteroids or
moons of their own "solar" system, greatly expanding the resources at
their disposal.

The panspermia project can be expected to start only after hundreds of
very likely candidates for abiogenesis were found, and no life found
on any of them.

B6. What if life is very common in our galaxy? What would that do to
the hypothesis of directed panspermia?

That would entirely depend on the origins of that life. If all
technological societies preceding ours were confronted with life in
the majority of suitable planets, I doubt that there would ever have
been a directed panspermia project.

B7. Didn't Crick and Orgel later repudiate directed panspermia on
somewhat similar grounds?

One talk.origins regular has claimed this, but the claim seems to rest
on a misleading juxtaposition of references [62] (the directed
panspermia paper) and [63] in the Wikipedia entry on Francis Crick,
where the entry addresses the hypothesis of directed panspermia.

[63] is a January 1993 joint paper by Crick and Orgel,

"Anticipating an RNA world. Some past
speculations on the origin of life: where are they today?". The FASEB
Journal 7 (1): 238-9. PMID 7678564

It can be read in scanned form at:

http://www.fasebj.org/content/7/1/238.long


This paper not only does not make any mention of directed panspermia,
it also makes no guesses as to the frequency or rarity of life in our
galaxy. Crick and Orgel merely acknowledge that RNA World hypothesis
had shown that an assumption they had made a number of years back was
obsolete.



At the end of this paper, they showed how they had NOT changed
their minds on one of the chief pieces of evidence they had given
for directed panspermia: the essential universality of the genetic
code:

Perhaps the most interesting
question concerns the nature of the interaction that led to
specific attachment of amino acids to primitive tRNAs. Was
the anticodon involved? If the answer is yes, then certain
codon assignments are predetermined. If the answer is no,
then the genetic code is a frozen accident. We still favor the
frozen accident theory, and we know of no convincing
evidence that argues against it.
http://www.fasebj.org/content/7/1/238.long

As the Wikipedia entry puts it:

"Crick and Orgel noted that they had been overly pessimistic about the
chances of abiogenesis on Earth when they had assumed that some kind
of self-replicating protein system was the molecular origin of life."

This is a reasonable inference from what they actually wrote, but that
is all.
They did NOT claim that this made them think abiogenesis is
commonplace in our galaxy, nor easily attained on the early earth. In
fact, in the same year that [63] was published, Orgel published
another joint article in which pessimism about RNA world was voiced:

Scientists interested in the origins of life seem to
divide neatly into two classes. The first, usually
but not always molecular biologists, believe that
RNA must have been the first replicating molecule
and that chemists are exaggerating the difficulty
of nucleotide synthesis. ... The second group
of scientists is much more pessimistic. They believe
that the de novo appearance of oligonucleotides on
the primitive earth would have been a near miracle.
(The authors subscribe to this latter view). Time
will tell which is correct.
--G. F. Joyce and Leslie E. Orgel, "Prospects
for understanding the origin of the RNA
world," in: _The RNA World_, ed. R. F.
Gesteland and J. F. Atkins, Cold Spring
Harbor Press, 1993, p. 19.



B8: Isn't directed panspermia essentially untestable, thereby removing
it from the category of science?

It is eminently testable *in principle*, and may also become testable
in practice if human beings make serious attempts to find out whether
there is life on other worlds. The following is mostly taken from

http://groups.google.com/group/talk.origins/msg/90027d90c58f7b4c


If we send enough probes, whether manned or unmanned, to
investigate the occurrence of life in many likely planets
in our galaxy, a lot of possibilities will be tested and
of the following four, only one will emerge the winner:


(1) We may find life in many stages of "protein takeover", all with
closely similar genetic codes.

That would be a big argument in favor of what I have called "the
Throomian sub-hypothesis." This has it that the panspermia project was
carried out by intelligent creatures that had ribozymes in place of
protein enzymes, and who carried out experiments in which they
replaced ribozymes incrementally with protein enzymes in organisms
over the course of thousands of years. They might have sent "the
latest models" to the planets they were seeding at that time.

On the other hand, if the takeover is in essentially the same stage as
that of earth, and the genetic code is very similar, that would
strongly support the overall hypothesis of directed panspermia while
all but falsifying the Throomian sub-hypothesis.

A third possible outcome is that we encounter lots of life with
genetic codes all very different from ours. That would all but
falsify all three main sub-hypotheses of directed panspermia,.

And finally, if we find no life after searching a million likely
planets, that would falsify the hypothesis that WE are the result of
evolution from unicellular organisms sent here by directed
panspermists, but would still leave my general hypothesis about the
frequency of directed panspermia largely unscathed.



B9: Is directed panspermia incompatible with Christian faith?

No, why should it be, when the Bible makes no mention of
microorganisms? Even if one takes an absolutely literalist view of
Genesis, the arrival of unicellular life on earth could be fit into
either the second day or the beginning of the third day of creation.

The plants that are mentioned on the third day are eukaryotes, which
function better if there is plenty of oxygen in the air. And, of
course, animals could not live without large amounts of oxygen. There
were only trace amounts of oxygen on earth when it was first formed,
and the oxygen that subsequently became an important component of the
atmosphere is due to photosynthesis, especially by cyanobacteria,
during the billions of years before the plant kingdom arose.

The theory of directed panspermia dovetails scientifically with the
theory of naturalistic evolution, but it is also compatible with God
creating every earth species after the first infusion. As for the
microorganisms sent by the panspermists, they in turn could have been
the product of divine creation, if one insists on going the whole nine
yards with species immutability.

Directed panspermia is even quite in the spirit of Genesis 6 through
8, where Noah is depicted as saving the animals from the great flood
and then (8: 17-19) sends them out from the ark to swarm and multiply
all over the earth. Substitute the spacecraft delivering the microbes
for the ark, and the analogy is very good.

NEXT: C: Connections with abiogenesis and intelligent design

[Ray Martinez]

Could you let us know when the section containing any physical
evidence supporting Directed Panspermia will be up?

Ray

[pnyikos]

Look at entry A7. The genetic code is pretty darn physical, although
the evidence certainly isn't enough to prove the DP hypothesis.

Before you are tempted to equate "no proof" with "no evidence," take a
look at B9, in the third post to this thread. It may help you decide
to stop wearing the camouflage of all the atheists who claim that
"there is no proof of God's existence" is equivalent to "there is no
evidence of God's existence."

You see, I think your motivation to wear this camouflage is emotional,
not rational, due to a strange inability to believe that DP is
compatible with Genesis 1 and species immutability. In my answer to
B9, I argue that it IS compatible.

By the way, I finally did a pair of replies to a November 24 post of
yours, about an hour ago, on the mis-named thread, "Peter Nyikos
defends evolution quite poorly."


Peter Nyikos

[Mark Isaak]

On 1/15/13 12:18 PM, pnyikos wrote:
> [...]

> B3. But doesn't Ockham's Razor strongly favor life abiotically
> produced on earth rather than by seeding by space aliens?
>
> Ockham's Razor decrees only that the most parsimonious explanation be
> given after ALL evidence has been scrutinized, and what little
> evidence there is [see the answer to A7], is on the side of directed
> panspermia.

A7 speaks to probability, not parsimony. And the little evidence does
not weigh to the side of dirPan because you left out A8, the evidence
*against* (which far outweighs the evidence in favor).

Getting back to parsimony, a theory in which life arose abiogenetically
is more parsimonious than a theory in which life arose abiogentically,
did some complicated evolving, and was shot across the stars. That
should be axiomatic -- A is always more parsimonious than A,B,C.

> B4. Why have we not found any evidence of space probes? Doesn't that
> count as evidence against directed panspermia?

> [...]

The answer is "Yes, although the evidence is very weak." You explained
why the evidence is very weak, but you left out the "yes."


> [...]

> B9: Is directed panspermia incompatible with Christian faith?

Has anyone ever brought up that question here?


--
Mark Isaak eciton (at) curioustaxonomy (dot) net
"It is certain, from experience, that the smallest grain of natural
honesty and benevolence has more effect on men's conduct, than the most
pompous views suggested by theological theories and systems." - D. Hume

[Earle Jones]

In article
<bb7c2611-937c-430e...@rm7g2000pbc.googlegroups.com>,

*
And, likewise, would you let us know when the section containing any
physical evidence supporting Intelligent Design will be up?

earle
*

[alias Ernest Major]

On 16/01/2013 02:12, Mark Isaak wrote:
> On 1/15/13 12:18 PM, pnyikos wrote:
>> [...]
>> B3. But doesn't Ockham's Razor strongly favor life abiotically
>> produced on earth rather than by seeding by space aliens?
>>
>> Ockham's Razor decrees only that the most parsimonious explanation be
>> given after ALL evidence has been scrutinized, and what little
>> evidence there is [see the answer to A7], is on the side of directed
>> panspermia.
>
> A7 speaks to probability, not parsimony. And the little evidence does
> not weigh to the side of dirPan because you left out A8, the evidence
> *against* (which far outweighs the evidence in favor).
>
> Getting back to parsimony, a theory in which life arose abiogenetically
> is more parsimonious than a theory in which life arose abiogentically,
> did some complicated evolving, and was shot across the stars. That
> should be axiomatic -- A is always more parsimonious than A,B,C.
>
>
>> B4. Why have we not found any evidence of space probes? Doesn't that
>> count as evidence against directed panspermia?
>> [...]
>
> The answer is "Yes, although the evidence is very weak." You explained
> why the evidence is very weak, but you left out the "yes."
>
>
>> [...]
>> B9: Is directed panspermia incompatible with Christian faith?
>
> Has anyone ever brought up that question here?
>

Ray Martinez?
>

[alias Ernest Major]

On 16/01/2013 00:23, pnyikos wrote:
> You see, I think your motivation to wear this camouflage is emotional,
> not rational, due to a strange inability to believe that DP is
> compatible with Genesis 1 and species immutability. In my answer to
> B9, I argue that it IS compatible.
>

Did you mean to claim this?

Directed panspermia is compatible with an allegorical interpretation of
Genesis 1 (but note that Ray claims to interpret Genesis literally).

But, unless you extend directed panspermia to include the implantation
of the complete contemporary biota it is not compatible with species
immutability. (I think that we can include Niven's bandersnatchi from
consideration given that the context is an explanation for the
Terrestrial biota.) Even then you have to explain where the panspermists
came from if species are immutable.

[pnyikos]

I'm doing Section C in two installments, with the second installment
to come tomorrow.

C: Connections with abiogenesis and intelligent design

C1: Does the ease or difficulty of abiogenesis have an effect on the
directed panspermia hypothesis?

Yes, but only on its probability, not the actual statement. The
effects on the probability are hinted at by the statement by Crick and
Orgel quoted in A7:

It seems unlikely that we would deliberately
send terrestrial organisms to planets
that we believed might already be inhabited.
However, in view of the precarious situation
on Earth, we might well be tempted to infect
other planets if we became convinced that
we were alone in the galaxy (Universe).
...
The hypothetical senders on another planet
may have been able to prove that they were
likely to be alone, and to remain so, or they
may have reached this conclusion mistakenly.
In either case, if they resembled us
psychologically, their motivation for polluting
the galaxy would be strong, if they believed
that all or even the great majority of
inhabitable planets could be given life by
Directed Panspermia.

-- Icarus 19 (1973) 341-346
http://profiles.nlm.nih.gov/ps/access/SCBCCP.pdf

The hypothesis that directed panspermia is more probable than
homegrown abiogenesis on any one planet rests largely on the following
contributing hypotheses, against which no convincing argument has
emerged to date:

(1) abiogenesis is a great rarity, expected to produce life evolving
to an intelligent species less than once in a galaxy and

(2) a good fraction of species like ours, on becoming convinced of
this, will undertake a massive project for spreading life to lifeless
worlds.

Here "massive" is of a magnitude to lead to the following conclusion:

(c) The odds of any one planet with intelligent life on it being the
result of panspermia are greater than those of it being due ultimately
to homegrown abiogenesis.


C2: How can one quantify "massive"?

To a great extent, that depends on how one defines "life" and,
consequently, "abiogenesis." Many would argue that something far, far
simpler than the simplest prokaryotes would qualify, like the simple,
diminutive "ur-cell" in the Ian Musgrave abiogenesis FAQ:

http://www.talkorigins.org/faqs/abioprob/abioprob.html

However, these ur-cells are very inefficient self-replicators, and
prokaryotes are hardy enough so that panspermists would send those
rather than "ur-cells" or something that simple, to give evolution a
huge head start.

And so, for this FAQ, I will use a working definition of "abiogenesis"
that asks for something in at least as good a position to evolve into
intelligent life as our prokaryotes.

C3: What is the reason for thinking that abiogenesis, in the above
sense, is such an extreme rarity as to make us alone in the galaxy
(Universe)?

First of all, it should be noted that Crick and Orgel did not
expressly endorse this line of thought, but neither have they ever
argued against it. See B2 and B7 of this FAQ for more details and
documentation, especially Orgel's opinion that the production
"oligonucleotides" being produced under abiotic conditions is a "near-
miracle." That is the first big hurdle to be overcome, and the
initial effect would even simpler and smaller than the "ur-cell" drawn
by Musgrave in his FAQ.

Then there are the many steps -- many of which have not even been
conjectured -- between an "ur-cell" as in that FAQ, and an organism
with a genetic code and a protein translation apparatus capable of
churning out even simple, long polypeptides.

And finally, there is the great difficulty of the "protein takeover"
proper, the most crucial element being the replacement of ribozymes
(or some other enzymatically active genetic material) with protein
enzymes (which are NOT genetic material).

C4: What's so difficult about the "protein takeover"?

In a word: specificity. And another: fidelity. How does an enzyme
capable e.g. of essentially always endowing CGA-anticodon tRNA
molecules with the amino acid (alanine) come to be? Until it has at
least as much fidelity as the non-protein enzyme that it is replacing,
it has a disruptive effect on the cell which produces it.

C5: What's so hard about such an enzyme being exapted from one that
performs a different function?

The question can be turned around: what's easy about it? Has anyone
even conjectured what could have been the function of the exapted
precursor of the enzyme (aa-tRNA synthetase, technically speaking)
described in the answer to the preceding question? Or guessed as to
how many exaptations there were on the road to this synthetase? That
is, how many distinct functions were involved in the precursors of
this synthetase? And where did the evolutionary chain begin -- a
structural protein with no specific function? a protein with many
different, inefficient enzymatic functions that later acquired some
specificity?

C6: Didn't Shapiro advance an alternative abiogenesis theory that gets
around these difficulties?

This has been hinted at in some descriptions of the October 2012 POTM,
which did not mention Shapiro by name, but clearly referred to a
theory that Shapiro outlined in a Scientific American article.

In reality, Shapiro's "small molecules" theory takes us no further
than (and perhaps not nearly as far as) the tiny "ur-cells" referenced
in C2. Moreover, Shapiro sounds very pessimistic about the prospects
of advancing even as far as "RNA world" and proposes no alternative
route to "life as we know it."

And so, paradoxically, Shapiro actually strengthens a radical form of
the directed panspermia hypothesis, with his suggestion that the
"small molecule" systems could result in "intelligent life as we do
not know it."

[pnyikos]

On Jan 15, 9:12�pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
> On 1/15/13 12:18 PM, pnyikos wrote:
>
> > [...]
> > B3. But doesn't Ockham's Razor strongly favor life abiotically
> > produced on earth rather than by seeding by space aliens?
>
> > Ockham's Razor decrees only that the most parsimonious explanation be
> > given after ALL evidence has been scrutinized, and what little
> > evidence there is [see the answer to A7], is on the side of directed
> > panspermia.
>
> A7 speaks to probability, not parsimony. �And the little evidence does
> not weigh to the side of dirPan because you left out A8, the evidence
> *against* (which far outweighs the evidence in favor).

You are looking in the wrong place. Section A is historical. It is
in Section B that I deal with objections that you don't mention here,
except for a simplistic view of the Razor that you give below.

Do you regularly play with the cards held this close to your chest?

> Getting back to parsimony, a theory in which life arose abiogenetically
> is more parsimonious than a theory in which life arose abiogentically,
> did some complicated evolving, and was shot across the stars.

Only if you take the myopic view. Crick and Orgel hypothesized a
massive project, which could easily mean -- assuming abiogenesis is a
once-in-a-galaxy event -- that planets with life on them are
overwhelmingly the product of directed paspermia. See the very end of
the answer to A7.

The quote I give there is repeated in C1, which I posted a few minutes
ago, and then the connection with abiogenesis made more explicit and
systematic later on in the answer to C1

>�That

> should be axiomatic -- A is always more parsimonious than A,B,C.

This abstract axiom has nothing to do with Ockham's Razor, properly
understood. See above.

> > B4. Why have we not found any evidence of space probes? �Doesn't that
> > count as evidence against directed panspermia?
> > [...]
>
> The answer is "Yes, although the evidence is very weak." �You explained
> why the evidence is very weak, but you left out the "yes."

I'll take that into consideration the next time I edit Section B.
Right now I am busy with the second half of my first draft for Section
C, and with the first draft of Section D, which I still hope to post
this week.

> > [...]
> > B9: Is directed panspermia incompatible with Christian faith?
>
> Has anyone ever brought up that question here?

Not exactly. Ray Martinez has, however, adamantly insisted, over and
over again, that the answer is NO.

I don't think you'll be surprised to say that this insistence
consisted exclusively of "pounding on the table," as an old adage
about attorneys has it. Now, in my answer to B9, I show how the facts
are against him.

Peter Nyikos

[pnyikos]

On Jan 16, 3:20�am, alias Ernest Major <{$t...@meden.demon.co.ukl>
wrote:

> On 16/01/2013 00:23, pnyikos wrote:
>
> > You see, I think your motivation to wear this camouflage is emotional,
> > not rational, due to a strange inability to believe that DP is
> > compatible with Genesis 1 and species immutability. �In my answer to
> > B9, I argue that it IS compatible.
>
> Did you mean to claim this?
>
> Directed panspermia is compatible with an allegorical interpretation of
> Genesis 1 (but note that Ray claims to interpret Genesis literally).

Have you read the answer to B9 yet? Where is the incompatibility with
a literal reading to be found?

Here, let me repeat B9, inasmuch as part of it is cut off in the
standard display of the old Google Groups (which I greatly prefer to
the New Google Groups).

B9: Is directed panspermia incompatible with Christian faith?

No, why should it be, when the Bible makes no mention of
microorganisms? Even if one takes an absolutely literalist view of
Genesis, the arrival of unicellular life on earth could be fit into
either the second day or the beginning of the third day of creation.

The plants that are mentioned on the third day are eukaryotes, which
function better if there is plenty of oxygen in the air. And, of
course, animals could not live without large amounts of oxygen. There
were only trace amounts of oxygen on earth when it was first formed,
and the oxygen that subsequently became an important component of the
atmosphere is due to photosynthesis, especially by cyanobacteria,
during the billions of years before the plant kingdom arose.

The theory of directed panspermia dovetails scientifically with the
theory of naturalistic evolution, but it is also compatible with God
creating every earth species after the first infusion. As for the
microorganisms sent by the panspermists, they in turn could have been
the product of divine creation, if one insists on going the whole nine
yards with species immutability.

Directed panspermia is even quite in the spirit of Genesis 6 through
8, where Noah is depicted as saving the animals from the great flood
and then (8: 17-19) sends them out from the ark to swarm and multiply
all over the earth. Substitute the spacecraft delivering the microbes
for the ark, and the analogy is very good.

> But, unless you extend directed panspermia to include the implantation
> of the complete contemporary biota it is not compatible with species
> immutability.

See the penultimate paragraph of the answer above, which was cut off
in the old Google Groups display with the usual "read more".

> (I think that we can include Niven's bandersnatchi from
> consideration given that the context is an explanation for the
> Terrestrial biota.) Even then you have to explain where the panspermists
> came from if species are immutable.

Abiogenesis on their home planet is where *I* put it. Special
creation on their home planet is where a species immutabilist would
put it.

Neither explanation is part of the DP hypothesis *per se*.

Peter Nyikos

[jillery]

I'm betting both of the above will happen sometime after Ray's book is
published.

[pnyikos]

On Jan 16, 2:04�pm, jillery <69jpi...@gmail.com> wrote:
> On Tue, 15 Jan 2013 21:09:33 -0800, Earle Jones
>
>
>
>
>
>
>
>
>

> <earle.jo...@comcast.net> wrote:
> >In article
> ><bb7c2611-937c-430e-8d3e-c23eba814...@rm7g2000pbc.googlegroups.com>,

> > Ray Martinez <pyramid...@yahoo.com> wrote:
>
> >> On Jan 15, 11:43�am, pnyikos <nyik...@bellsouth.net> wrote:
> >> > I am starting a new thread for my FAQ on directed panspermia, but will
> >> > also be tying up some loose ends on the first thread that I devoted to
> >> > this topic late last autumn. �Today I will be posting a slightly
> >> > revised Section A and a slightly longer Section B. �Then tomorrow, �I
> >> > will post my first draft for Section C, and I hope also to post a
> >> > first draft for Section D this week. �Here are what these sections are
> >> > about:
>
> >> > A. Origins of the Theory of Directed Panspermia
>
> >> > B. �Some Pointed Questions about Directed Panspermia
>
> >> > C: Connections with abiogenesis and intelligent design
>
> >> > D. Delivery Systems
>
> >> > There is at least one more section in the planning stages, but I'd be
> >> > starting a new thread for those.
>
> >> > Peter Nyikos
> >> > Professor, Dept. of Mathematics � � � -- standard disclaimer--
> >> > University of South Carolinahttp://www.math.sc.edu/~nyikos/
> >> > nyikos @ math.sc.edu
>
> >> Could you let us know when the section containing any physical
> >> evidence supporting Directed Panspermia will be up?

I answered that in my own reply to Martinez:

_________begin repost__________

Look at entry A7. The genetic code is pretty darn physical,
although the evidence certainly isn't enough to prove the DP
hypothesis.

Before you are tempted to equate "no proof" with "no evidence,"
take a look at B9, in the third post to this thread. It may help you
decide to stop wearing the camouflage of all the atheists who claim
that "there is no proof of God's existence" is equivalent to "there is
no
evidence of God's existence."

=================== end of repost

> >> Ray
>
> >*
> >And, likewise, would you let us know when the section containing any
> >physical evidence supporting Intelligent Design will be up?

I actually made a start to that in the answer to B4. More to come in
the second half of Section C.

> I'm betting both of the above will happen sometime after Ray's book is
> published.

I'm betting that jillery, who has conveniently killfiled me, will
conveniently ignore any reply that preserves what I wrote to Ray
Martinez or what I am writing here.

Peter Nyikos

[pnyikos]

Re-reading my reply to Mark Isaak, I see that I missed a big lapse in
his logic. In this second reply I point it out and correct it.

On Jan 15, 9:12�pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:

> On 1/15/13 12:18 PM, pnyikos wrote:
>
> > [...]
> > B3. But doesn't Ockham's Razor strongly favor life abiotically
> > produced on earth rather than by seeding by space aliens?
>
> > Ockham's Razor decrees only that the most parsimonious explanation be
> > given after ALL evidence has been scrutinized, and what little
> > evidence there is [see the answer to A7], is on the side of directed
> > panspermia.

[snip things dealt with in first reply.

> Getting back to parsimony, a theory in which life arose abiogenetically

abiogenetically ON EARTH.

> is more parsimonious than a theory in which life arose abiogentically,

SOMEWHERE in our galaxy. And with perhaps billions of planets with
good conditions for preserving life once it is established, the
probability of the first is microscopic compared to that for the
second.

> did some complicated evolving,

That does cut the odds down, but perhaps not nearly enough to suit
you, Mark.

> and was shot across the stars.

Correction: the complicated panspermists shot much simpler organisms
"across the stars".

> That
> should be axiomatic -- A is always more parsimonious than A,B,C.

But what we are dealing with is something far removed from this: your
first A is utterly different from your second A.

Peter Nyikos

[pnyikos]

On Jan 16, 1:03�pm, pnyikos <nyik...@bellsouth.net> wrote:


> � � � C: Connections with abiogenesis and intelligent design

The first installment had to do with connections with abiogenesis. Now
comes the second installment, connecting with intelligent design.

I've repeated the last entry (with two small additions) in the first
installment to establish continuity.

> C6: Didn't Shapiro advance an alternative abiogenesis theory that gets
> around these difficulties?
>
> This has been hinted at in some descriptions of the October 2012 POTM,
> which did not mention Shapiro by name, but clearly referred to a
> theory that Shapiro outlined in a Scientific American article.

"A Simpler Origin for Life," by Robert Shapiro, February 12, 2007
http://www.scientificamerican.com/article.cfm?id=a-simpler-origin-for-life&offset=7>

> In reality, Shapiro's "small molecules" theory takes us no further
> than (and perhaps not nearly as far as) the tiny "ur-cells" referenced
> in C2. Moreover, Shapiro sounds very pessimistic about the prospects
> of advancing even as far as "RNA world" and proposes no alternative
> route to "life as we know it."
>
> And so, paradoxically, Shapiro actually strengthens a radical form of
> the directed panspermia hypothesis, with his suggestion that the
> "small molecule" systems could result in "intelligent life as we do
> not know it."

And this intelligent life might, in turn, design "life as we know it"
and spread it to many places in the galaxy, including earth.

.

C7: This sounds like Intelligent Design (ID) theory, but hasn't ID
theory been ruled to be "not science" and to have only the effect of
advancing religion, in the landmark case *Kitzmiller v. Dover*?

This could just be a matter of semantics. Certainly there is nothing
religious about hypotesizing that naturally arising intelligent
species designed a new form of life. We might eventually do something
similar ourselves.

.

C8: Why would panspermists invent life forms based on radically
different biochemistry from their own?

The new life forms could just be a serendipitous by-product of
nanotechnology. After all, the protein translation mechanism has often
been likened to a factory assembly line, and some form of it may have
started out that way.

This mechanism would have been used similarly to our own translation
mechanism, to churn out various kinds of useful proteins, in the form
of polypeptides coded into strands of mRNA. As these proteins got
more sophisticated, they were used in turn to replace some of the
components of the "assembly line" so that the process became more and
more automated. These proteins could also have been used to produce
DNA encoding the mRNA strands and the tRNA molecules and the
ribosomes, and soon the route to a self-replicating organism similar
to our simpler prokaryotes would have become clear.

The panspermists may have started out sending organized multicellular
forms of their kind of life to other planets already, then possibly
realized that these unicellular forms of "life as they hadn't known it
up to then" were hardier and could be sent to more distant planets.

.

C9: Is, then, intelligent design an integral part of directed
panspermia theory?

No, because there are many alternative possibilities for the nature of
the panspermists and the kinds of life they sent -- one of which, of
course, was our own kinds of microorganisms. The first alternative
completely dispenses with ID:

(1) The most conservative is that they simply selected naturally
occurring microorganisms that seemed best able to both survive the
rigors of the journey and to establish themselves on the target
planet, and to make the selection dependent on the physical
characteristics of the target planet.

(2) They might have done as in (1) but also carried out genetic
engineering on a level that is already being practiced by us here on
earth.

(3) The genetic engineering might have been well in advance of what we
are capable of today, but not enough to tamper with the basic
biochemistry of the organisms involved. As Francis Crick put it in
his 1981 book, _Life Itself_:

The senders could well have developed wholly new
strains of microorganisms, specially designed
to cope with prebiotic conditions, though
whether it would have been better to try to
combine all the desirable properties within
one single type of organism or to send many
different organisms is not completely clear.

(4) The panspermists, and the life around them, may have been based on
a simpler genetic code, with as few as four different amino acids, but
based on DNA, protein enzymes, and using the same basic ingredients
for protein translation (mRNA, tRNA, ribosomes, aa-tRNA synthetases,
EF-Tu, and a few other necessities) as our own life. Then, by
degrees, other amino acids and corresponding RNA molecules and
synthetases could have been designed and incorporated into the genomes
of the microorganisms they sent. With each new seeding, they might

have sent "the latest models" to the planets they were seeding at that
time.

(5) The "Throomian" sub-hypothesis, mentioned in B8: the panspermia

project was carried out by intelligent creatures that had ribozymes in

place of protein enzymes, but otherwise had the same basic ingredients
listed in (4). In particular, only simpler (mostly structural)
proteins were naturally produced in their bodies. In this sub-
hypothesis, they carried out experiments in which they replaced

ribozymes incrementally with protein enzymes in organisms over the
course of thousands of years.

(6) And finally, there is the possibility of our own microorganisms
being designed by an intelligent species built on cells that are
radically different from our own, described in C8, and perhaps much
simpler than our own. These include the "ur-cells" and "small molecule
systems" mentioned above, or the "lipid vesicles" of Marc Tessera.

Next:
Section D: Delivery Systems

[Mark Isaak]

On 1/16/13 10:12 AM, pnyikos wrote:
> On Jan 15, 9:12 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
>> On 1/15/13 12:18 PM, pnyikos wrote:
>>
>>> [...]
>>> B3. But doesn't Ockham's Razor strongly favor life abiotically
>>> produced on earth rather than by seeding by space aliens?
>>
>>> Ockham's Razor decrees only that the most parsimonious explanation be
>>> given after ALL evidence has been scrutinized, and what little
>>> evidence there is [see the answer to A7], is on the side of directed
>>> panspermia.
>>
>> A7 speaks to probability, not parsimony. And the little evidence does
>> not weigh to the side of dirPan because you left out A8, the evidence
>> *against* (which far outweighs the evidence in favor).
>
> You are looking in the wrong place. Section A is historical. It is
> in Section B that I deal with objections that you don't mention here,
> except for a simplistic view of the Razor that you give below.

Whatever. It still seems to me that evidence for and evidence against
should be adjacent, but it's your FAQ.

> Do you regularly play with the cards held this close to your chest?

You mean, do I not repeat myself endlessly? No, I don't. Besides, it
is your job to look for and keep track of the evidence against directed
panspermia.

>> Getting back to parsimony, a theory in which life arose abiogenetically
>> is more parsimonious than a theory in which life arose abiogentically,
>> did some complicated evolving, and was shot across the stars.
>
> Only if you take the myopic view. Crick and Orgel hypothesized a
> massive project, which could easily mean -- assuming abiogenesis is a
> once-in-a-galaxy event -- that planets with life on them are
> overwhelmingly the product of directed paspermia. See the very end of
> the answer to A7.

See that word "assuming" up there? As soon as you introduce it,
parsimony leaves by another door.

> The quote I give there is repeated in C1, which I posted a few minutes
> ago, and then the connection with abiogenesis made more explicit and
> systematic later on in the answer to C1
>
>> That
>> should be axiomatic -- A is always more parsimonious than A,B,C.
>
> This abstract axiom has nothing to do with Ockham's Razor, properly
> understood. See above.

Ockham's razor says (slightly paraphrased), "Do not multiply entities
without necessity." Even you can see that you are multiplying entities.
And you are doing so without necessity. You *assume* there is
necessity, but that assumption is unsupportable; or at best, it is far
out of proportion with all the entities you have added.

[Mark Isaak]

On 1/16/13 12:02 PM, pnyikos wrote:
> Re-reading my reply to Mark Isaak, I see that I missed a big lapse in
> his logic. In this second reply I point it out and correct it.
>
> On Jan 15, 9:12 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
>> On 1/15/13 12:18 PM, pnyikos wrote:
>>
>>> [...]
>>> B3. But doesn't Ockham's Razor strongly favor life abiotically
>>> produced on earth rather than by seeding by space aliens?
>>
>>> Ockham's Razor decrees only that the most parsimonious explanation be
>>> given after ALL evidence has been scrutinized, and what little
>>> evidence there is [see the answer to A7], is on the side of directed
>>> panspermia.
>
> [snip things dealt with in first reply.
>
>> Getting back to parsimony, a theory in which life arose abiogenetically
>
> abiogenetically ON EARTH.
>
>> is more parsimonious than a theory in which life arose abiogentically,
>
> SOMEWHERE in our galaxy.

Okay, you have a point. Multiple other planets are not directly
comparable to the single planet earth, and, since they are known to
exist, they would not bother Ockham.

> And with perhaps billions of planets with
> good conditions for preserving life once it is established, the
> probability of the first is microscopic compared to that for the
> second.
>
>> did some complicated evolving,
>
> That does cut the odds down, but perhaps not nearly enough to suit
> you, Mark.

As I pointed out when I did the actual calculations a year or two ago,
the odds are so very uncertain that they cannot enter the picture.
Unless they picture you are painting is a fantasy landscape.

>> and was shot across the stars.
>
> Correction: the complicated panspermists shot much simpler organisms
> "across the stars".

You quibble. Evolving and shooting are both essential parts of the
scenario.

>> That
>> should be axiomatic -- A is always more parsimonious than A,B,C.
>
> But what we are dealing with is something far removed from this: your
> first A is utterly different from your second A.

Still, dirPan introduces several unknown entities, and the known odds
(or rather, lack of them) show that those entities buy you nothing in
return, except entertainment. DirPan is still disfavored by Ockham's Razor.

[Mark Isaak]

On 1/16/13 10:03 AM, pnyikos wrote:
> I'm doing Section C in two installments, with the second installment
> to come tomorrow.
>
> C: Connections with abiogenesis and intelligent design
>
> C1: Does the ease or difficulty of abiogenesis have an effect on the
> directed panspermia hypothesis?
>

> Yes, but only on its probability, not the actual statement. [...]

This contradicts the calculations I made last year.

Here's a large section of that post again:

--- [begin]
First, definition of the relevant variables:

pA = probability of Abiogenesis. More specifically, the probability,
given an earth-like planet, of life arising to a population and
robustness that, short of a cosmic catastrophe, it will not go
extinct for millions of years at least.
pP = probability of successful Pansperia. That is, the probability
that a single panspermia attempt on an earth-like planet will
result in life as described above.
pT = probability of Technological capability. Specifically, the
probability that, given life as described above, it will evolve
and develop a race technically capable of doing panspermia.
pS = probability, given the technical capability, that a race will
in fact attempt at least one panspermia seeding.
N = expected number of panspermia attempts by a race which is attempting
panspermia. By definition, N >= 1.
U = number of earth-like planets in the universe.

Thus, analogous to the Drake equation, we have

Number of planets alive by abiogenesis =
La = U * pA
Number of planets alive by pansperia =
Lp = U * pA * pT * pS * N * pP
Probability that a planet's life arose by panspermia = Lp / (Lp + La)

Note that Lp does not take into account second-generation panspermia --
panspermia from planets whose life originated by panspermia. There are
two reasons for this. First, it is questionable whether the universe is
old enough for life to evolve up to technical intelligence twice in
sequence. Second, given the uncertainties we already have, the issue is
moot. If panspermia is common, second-generation panspermia could add
to it, but if it is unlikely, a second generation would not make much of
a difference.

So what can we conclude? First, the probability that a planet's life
originated by panspermia is not affected by the probability of abiogenesis.

The factors that the probability *does* depend on are all unknown. Our
speculation on what might be reasonable values for pT, pS, N, and pP
need not be completely uninformed, but we really have very little to go on.
--- [end]

So, barring second-generation panspermia, the ease or difficulty of
abiogenesis *does not* have an effect on the directed panspermia hypothesis.

[pnyikos]

On Jan 17, 3:20嚙緘m, Mark Isaak <eci...@curioustax.onomy.net> wrote:
> On 1/16/13 12:02 PM, pnyikos wrote:

> > Re-reading my reply to Mark Isaak, 嚙瘢 see that I missed a big lapse in
> > his logic. 嚙瘢n this second reply I point it out and correct it.

>
> > On Jan 15, 9:12 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
> >> On 1/15/13 12:18 PM, pnyikos wrote:
>
> >>> [...]
> >>> B3. But doesn't Ockham's Razor strongly favor life abiotically
> >>> produced on earth rather than by seeding by space aliens?
>
> >>> Ockham's Razor decrees only that the most parsimonious explanation be
> >>> given after ALL evidence has been scrutinized, and what little
> >>> evidence there is [see the answer to A7], is on the side of directed
> >>> panspermia.
>
> > [snip things dealt with in first reply.
>
> >> Getting back to parsimony, a theory in which life arose abiogenetically
>
> > abiogenetically ON EARTH.
>
> >> is more parsimonious than a theory in which life arose abiogentically,
>
> > SOMEWHERE in our galaxy.
>

> Okay, you have a point. 嚙瞎ultiple other planets are not directly

> comparable to the single planet earth, and, since they are known to
> exist, they would not bother Ockham.
>
> > And with perhaps billions of planets with
> > good conditions for preserving life once it is established, the
> > probability of the first is microscopic compared to that for the
> > second.

However, these probabilities are part of a red herring. Barring
supernatural creation, we KNOW abiogenesis took place somewhere, and
almost surely somewhere in our galaxy. The probability of directed
panspermia is a conditional one: GIVEN that abiogenesis took place,
what is the probability that it took place on earth?

That's what your analogue of the Drake equation was meant to address.
I see you alluding to it below.

> >> did some complicated evolving,
>
> > That does cut the odds down, but perhaps not nearly enough to suit
> > you, Mark.
>
> As I pointed out when I did the actual calculations a year or two ago,
> the odds are so very uncertain that they cannot enter the picture.

That need not stop us from guessing at them. After all, Carl Sagan
made numerical guesses for the unknowns in the original Drake
equation, and gave them in _Cosmos_, and even gave some explanation
for why he chose those numbers.

> Unless they picture you are painting is a fantasy landscape.

Sagan was never deterred from painting fantasy landscapes. His
_Cosmos_ TV series used a number of them. Some of them are reprinted
in the book by him with the same title.

> >> and was shot across the stars.
>
> > Correction: the complicated panspermists shot much simpler organisms
> > "across the stars".
>
> You quibble.

I guess you missed Paul Gans repeatedly asking how microbes could
build and pilot a spaceship, and Walter Bushell either humoring him or
thinking he was humoring me.

As another regular is fond of saying, "You can't make this junk up."

> Evolving and shooting are both essential parts of the
> scenario.

Absolutely. And the question of how likely prokaryotes are to evolve
into an intelligent species like ourselves plays a crucial part in
trying to judge which is more likely, earthly abiogenesis or directed
panspermia.

> >> That
> >> should be axiomatic -- A is always more parsimonious than A,B,C.
>
> > But what we are dealing with is something far removed from this: your
> > first A is utterly different from your second A.
>
> Still, dirPan introduces several unknown entities, and the known odds
> (or rather, lack of them) show that those entities buy you nothing in

> return, except entertainment. 嚙瘩irPan is still disfavored by Ockham's Razor.

I beg to differ. Look at the "assembly line" scenario in the answer
to C8 in my FAQ draft. That is one conceivable way we ourselves might
invent new life that is very different from our own. A less
speculative way is to play the following scenario in reverse, by
incrementally replacing protein enzymes with ribozymes:

(5) The "Throomian" sub-hypothesis, mentioned in B8: the panspermia

project was carried out by intelligent creatures that had ribozymes in

place of protein enzymes, but otherwise had the same basic ingredients
listed in (4). In particular, only simpler (mostly structural)
proteins were naturally produced in their bodies. In this sub-

hypothesis, they carried out experiments in which they replaced

ribozymes incrementally with protein enzymes in organisms over the
course of thousands of years.

The above paragraph is taken from my answer to C9, which gives one of
six possibilities for what those "unknown entities" may have been and
done.

Peter Nyikos

[pnyikos]

On Jan 17, 2:53�pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
> On 1/16/13 10:12 AM, pnyikos wrote:

> > On Jan 15, 9:12 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
> >> On 1/15/13 12:18 PM, pnyikos wrote:
>
> >>> [...]
> >>> B3. But doesn't Ockham's Razor strongly favor life abiotically
> >>> produced on earth rather than by seeding by space aliens?
>
> >>> Ockham's Razor decrees only that the most parsimonious explanation be
> >>> given after ALL evidence has been scrutinized, and what little
> >>> evidence there is [see the answer to A7], is on the side of directed
> >>> panspermia.
>
> >> A7 speaks to probability, not parsimony. �And the little evidence does
> >> not weigh to the side of dirPan because you left out A8, the evidence
> >> *against* (which far outweighs the evidence in favor).
>
> > You are looking in the wrong place. �Section A is historical. �It is
> > in Section B that I deal with objections that �you don't mention here,
> > except for a simplistic view of the Razor that you give below.

What Section A does is mention the evidence Crick and Orgel dealt
with, and in that original Icarus article, it's all for DP, unless one
accepts the hypothesis that abiogenesis is quite common.

> Whatever. �It still seems to me that evidence for and evidence against
> should be adjacent, but it's your FAQ.

> > Do you regularly play with the cards held this close to your chest?
>
> You mean, do I not repeat myself endlessly?

Don't be daft. You talk about the evidence against "far outweighing"
the evidence for, but fail to even mention any of that "outweighing"
evidence, except as noted below.

>�No, I don't. �Besides, it

> is your job to look for and keep track of the evidence against directed
> panspermia.

I've looked for it in the many threads that have been devoted to the
subject, and I think I've given most of the ones I've found in Section
B, except for those dealing with spaceflight, which will be in Section
D.

> >> Getting back to parsimony, a theory in which life arose abiogenetically
> >> is more parsimonious than a theory in which life arose abiogentically,
> >> did some complicated evolving, and was shot across the stars.
>
> > Only if you take the myopic view. �Crick and Orgel hypothesized a
> > massive project, which could easily mean -- assuming abiogenesis is a
> > once-in-a-galaxy event �-- that planets with life on them are
> > overwhelmingly the product of directed paspermia. �See the very end of
> > the answer to A7.
>
> See that word "assuming" up there? �As soon as you introduce it,
> parsimony leaves by another door.

Huh? Do you think it is more parsimonious to assume that abiogenesis
occurs very frequently?

[snip]

> Ockham's razor says (slightly paraphrased), "Do not multiply entities
> without necessity."

>�Even you can see that you are multiplying entities.

The main alternative is to assume that we are the first intelligent
species to evolve in the whole galaxy, or at least that the first one
evolved after life on earth began. How reasonable do you think that
is?

[snip]

Peter Nyikos

[Paul J Gans]

Added note: the number of planets in our galaxy alone is now
estimated as 100 billion as a LOWER LIMIT. Better estimates
range up to two or three TRILLION. How many of those are
"earth like" is not known, but there is no reason to think the
number small.

See:

http://scienceblogs.com/startswithabang/2013/01/05/how-many-planets-are-in-the-universe/


--
--- Paul J. Gans

[Paul J Gans]

pnyikos <nyi...@bellsouth.net> wrote:

>On Jan 17, 3:20?pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
>> On 1/16/13 12:02 PM, pnyikos wrote:

>> > Re-reading my reply to Mark Isaak, ?I see that I missed a big lapse in
>> > his logic. ?In this second reply I point it out and correct it.

>>
>> > On Jan 15, 9:12 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
>> >> On 1/15/13 12:18 PM, pnyikos wrote:
>>
>> >>> [...]
>> >>> B3. But doesn't Ockham's Razor strongly favor life abiotically
>> >>> produced on earth rather than by seeding by space aliens?
>>
>> >>> Ockham's Razor decrees only that the most parsimonious explanation be
>> >>> given after ALL evidence has been scrutinized, and what little
>> >>> evidence there is [see the answer to A7], is on the side of directed
>> >>> panspermia.
>>
>> > [snip things dealt with in first reply.
>>
>> >> Getting back to parsimony, a theory in which life arose abiogenetically
>>
>> > abiogenetically ON EARTH.
>>
>> >> is more parsimonious than a theory in which life arose abiogentically,
>>
>> > SOMEWHERE in our galaxy.
>>

>> Okay, you have a point. ?Multiple other planets are not directly

>> comparable to the single planet earth, and, since they are known to
>> exist, they would not bother Ockham.
>>
>> > And with perhaps billions of planets with
>> > good conditions for preserving life once it is established, the
>> > probability of the first is microscopic compared to that for the
>> > second.

>However, these probabilities are part of a red herring. Barring
>supernatural creation, we KNOW abiogenesis took place somewhere, and
>almost surely somewhere in our galaxy. The probability of directed
>panspermia is a conditional one: GIVEN that abiogenesis took place,
>what is the probability that it took place on earth?

What you have above is a red herring. You left out one
major condition, namely the only planet we know that does
have life is earth. That changes the odds dramatically.

[snip for focus and brevity]

[pnyikos]

On Jan 17, 4:32 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:

> On 1/16/13 10:03 AM, pnyikos wrote:
> > C: Connections with abiogenesis and intelligent design

> > C1: Does the ease or difficulty of abiogenesis have an effect on the
> > directed panspermia hypothesis?

> > Yes, but only on its probability, not the actual statement. [...]

> This contradicts the calculations I made last year.

Yes, but those calculations were based on a highly dubious assumption:
that certain events are independent and hence the law of
multiplication of probabilities applies.

> Here's a large section of that post again:

> --- [begin]
> First, definition of the relevant variables:

> pA = probability of Abiogenesis. More specifically, the probability,
> given an earth-like planet, of life arising to a population and
> robustness that, short of a cosmic catastrophe, it will not go
> extinct for millions of years at least.
> pP = probability of successful Pansperia. That is, the probability
> that a single panspermia attempt on an earth-like planet will
> result in life as described above.
> pT = probability of Technological capability. Specifically, the
> probability that, given life as described above, it will evolve
> and develop a race technically capable of doing panspermia.
> pS = probability, given the technical capability, that a race will
> in fact attempt at least one panspermia seeding.

Here is one flaw: You are assuming A and S are independent events
in your equations below. They are not. If pA is high, pS is low, and
vice versa. Here is how Crick and Orgel put it:

It seems unlikely that we would deliberately
send terrestrial organisms to planets
that we believed might already be inhabited.
However, in view of the precarious situation
on Earth, we might well be tempted to infect
other planets if we became convinced that
we were alone in the galaxy (Universe).
...
The hypothetical senders on another planet
may have been able to prove that they were
likely to be alone, and to remain so, or they
may have reached this conclusion mistakenly.
In either case, if they resembled us
psychologically, their motivation for polluting
the galaxy would be strong, if they believed
that all or even the great majority of
inhabitable planets could be given life by
Directed Panspermia.

> N = expected number of panspermia attempts by a race which is attempting
> panspermia. By definition, N >= 1.

And again, if pA is very small, N can be expected to be very large,
and vice versa. The reasoning is similar to that above. Note that
Crick and Orgel say "polluting the galaxy" and not just "polluting one
or more planets."

> U = number of earth-like planets in the universe.

> Thus, analogous to the Drake equation, we have

> Number of planets alive by abiogenesis =
> La = U * pA
> Number of planets alive by pansperia =
> Lp = U * pA * pT * pS * N * pP

If pA is low, S is much more likely than if pA is high. The upshot is
that p(A n S) is not the same as pA*pS, if one takes pS without
reference to how high or low pA is. So the equation breaks down.

> Probability that a planet's life arose by panspermia = Lp / (Lp + La)

...and that could be close to one (1) if pS and pN are large and pA is
small, or close to 0 (zero) if pA is large and pS and N are small.

[snip comments about second-generation panspermia, about which we are
largely in agreement]

> So what can we conclude? First, the probability that a planet's life
> originated by panspermia is not affected by the probability of abiogenesis.

Wrong: pA affects pS and N, according to Crick and Orgel (and myself)
and therefore one will get different answers for the quotient
depending on what pA is.

[snip rest]

Peter Nyikos

[pnyikos]

On Jan 17, 7:18�pm, Paul J Gans <gan...@panix.com> wrote:

No, I just didn't say everything I could have said at that point. See
below for the rest.

>�You left out one

> major condition, namely the only planet we know that does
> have life is earth.

The condition has no bearing on the fundamental question: if a planet
has life, what are the odds that this life arose by abiogenesis on
that planet versus its arising by panspermia?

Our earth satisfies the "if" clause, and we move on to the rest of the
question as applied to earth.

> That changes the odds dramatically.

On the contrary, whatever the odds are, the case of earth is one
application of the odds, which are unaffected by a given application
thereof.

> [snip for focus and brevity]

Thanks, that was actually a big help.

Peter Nyikos

[Mark Isaak]

On 1/17/13 1:37 PM, pnyikos wrote:

> On Jan 17, 3:20 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
>> On 1/16/13 12:02 PM, pnyikos wrote:
>

>>> Re-reading my reply to Mark Isaak, I see that I missed a big lapse in
>>> his logic. In this second reply I point it out and correct it.

>>
>>> On Jan 15, 9:12 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
>>>> On 1/15/13 12:18 PM, pnyikos wrote:
>>
>>>>> [...]
>>>>> B3. But doesn't Ockham's Razor strongly favor life abiotically
>>>>> produced on earth rather than by seeding by space aliens?
>>
>>>>> Ockham's Razor decrees only that the most parsimonious explanation be
>>>>> given after ALL evidence has been scrutinized, and what little
>>>>> evidence there is [see the answer to A7], is on the side of directed
>>>>> panspermia.
>>
>>> [snip things dealt with in first reply.
>>
>>>> Getting back to parsimony, a theory in which life arose abiogenetically
>>
>>> abiogenetically ON EARTH.
>>
>>>> is more parsimonious than a theory in which life arose abiogentically,
>>
>>> SOMEWHERE in our galaxy.
>>

>> Okay, you have a point. Multiple other planets are not directly

Is that your goal, then? Speculative fiction?

>>>> and was shot across the stars.
>>
>>> Correction: the complicated panspermists shot much simpler organisms
>>> "across the stars".
>>
>> You quibble.
>
> I guess you missed Paul Gans repeatedly asking how microbes could
> build and pilot a spaceship, and Walter Bushell either humoring him or
> thinking he was humoring me.
>
> As another regular is fond of saying, "You can't make this junk up."
>
>> Evolving and shooting are both essential parts of the
>> scenario.
>
> Absolutely. And the question of how likely prokaryotes are to evolve
> into an intelligent species like ourselves plays a crucial part in
> trying to judge which is more likely, earthly abiogenesis or directed
> panspermia.
>
>>>> That
>>>> should be axiomatic -- A is always more parsimonious than A,B,C.
>>
>>> But what we are dealing with is something far removed from this: your
>>> first A is utterly different from your second A.
>>
>> Still, dirPan introduces several unknown entities, and the known odds
>> (or rather, lack of them) show that those entities buy you nothing in

>> return, except entertainment. DirPan is still disfavored by Ockham's Razor.

>
> I beg to differ. Look at the "assembly line" scenario in the answer
> to C8 in my FAQ draft.

You just don't get it. Your assembly line scenario is yet another
entity you add to Ockham's beard. Fine for writing science fiction, but
not for much else.

[Paul J Gans]

pnyikos <nyi...@bellsouth.net> wrote:

>> >However, these probabilities are part of a red herring. ?Barring

>> >supernatural creation, we KNOW abiogenesis took place somewhere, and

>> >almost surely somewhere in our galaxy. ?The probability of directed

>> >panspermia is a conditional one: GIVEN that abiogenesis took place,
>> >what is the probability that it took place on earth?
>>
>> What you have above is a red herring.

>No, I just didn't say everything I could have said at that point. See
>below for the rest.

>>?You left out one

>> major condition, namely the only planet we know that does
>> have life is earth.

>The condition has no bearing on the fundamental question: if a planet
>has life, what are the odds that this life arose by abiogenesis on
>that planet versus its arising by panspermia?

That is NOT the question you asked, nor is it the one to
which I responded. You wrote;

"GIVEN that abiogenesis took place, what is the probability that
it took place on earth?"

I point out again that the answer to this is strongly
influenced by the fact that we DO have life on earth.

>Our earth satisfies the "if" clause, and we move on to the rest of the
>question as applied to earth.

>> That changes the odds dramatically.

>On the contrary, whatever the odds are, the case of earth is one
>application of the odds, which are unaffected by a given application
>thereof.

Peter, don't muddy the water. One reason why folks do not
like discussing anything with you is that you are very
slippery. What you wrote was clear (it is still up there)
and what I responded was clear (it is still up there). This
post can be read as an attempt on your part to evade a major
blunder. I won't read it that way. But I did expect a
serious response.

[pnyikos]

> >> >almost surely somewhere in our galaxy. The probability of directed

> >> >panspermia is a conditional one: GIVEN that abiogenesis took place,
> >> >what is the probability that it took place on earth?
>
> >> What you have above is a red herring.

You ignored what I said here, Paul:

> >No, I just didn't say everything I could have said at that point.  See
> >below for the rest.


> >>?You left out one
> >> major condition, namely the only planet we know that does
> >> have life is earth.

This statement of yours says nothing special about the earth itself
except that we happen to live on it. So the analysis I gave below is
airtight--unless you can bring in other properties of earth that may
make it necessary to modify it.

> >The condition has no bearing on the fundamental question: if a planet
> >has life, what are the odds that this life arose by abiogenesis on
> >that planet versus its arising by panspermia?
>
> That is NOT the question you asked, nor is it the one to
> which I responded.

Well, duh. What you are responding to NOW is the really fundamental
question. See my next comment.

> You wrote;
>
>   "GIVEN that abiogenesis took place, what is the probability that
>    it took place on earth?"

The really fundamental question has

"on *any* given planet on which life exists"

in place of "on earth".

The earth is simply an example of such a planet. The fact that WE
don't know of any other such planet is irrelevant to the issue of
whether life on earth is the result of earthly abiogenesis, or
panspermia.

> I point out again that the answer to this is strongly
> influenced by the fact that we DO have life on earth.

Well, duh again: if there were no life on earth, the whole question of
whether life on earth is due to abiogenesis or directed panspermia
would become MEANINGLESS.

> >Our earth satisfies the "if" clause, and we move on to the rest of the
> >question as applied to earth.
> >> That changes the odds dramatically.
> >On the contrary, whatever the odds are, the case of earth is one
> >application of the odds, which are unaffected by a given application
> >thereof.

[snip unsupported accusation, and sequel]

Peter Nyikos

[Mitchell Coffey]

Nonsense: we know that life is possible on Earth, and that it was
possible on Earth for life to evolve to include intelligent beings, and
that on Earth conditions are such that wealthy industrial civilizations
capable of space travel are possible. We know this is possible on Earth.
You need to demonstrate that the probabilities that these may happen
elsewhere are high enough to make DP probable.

>> I point out again that the answer to this is strongly
>> influenced by the fact that we DO have life on earth.
>
> Well, duh again: if there were no life on earth, the whole question of
> whether life on earth is due to abiogenesis or directed panspermia
> would become MEANINGLESS.

[snip]

You should discuss this with our resident Bayesian.

Mitchell Coffey

[Mitchell Coffey]

On 1/17/2013 5:18 PM, pnyikos wrote:

> On Jan 17, 4:32 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
>> On 1/16/13 10:03 AM, pnyikos wrote:
>
>>> C: Connections with abiogenesis and intelligent design
>>
>>> C1: Does the ease or difficulty of abiogenesis have an effect on the
>>> directed panspermia hypothesis?
>>
>>> Yes, but only on its probability, not the actual statement. [...]
>>
>> This contradicts the calculations I made last year.
>

> No, it only contradicts a conclusion you drew from them, after failing
> to note an important point.

>
>> Here's a large section of that post again:
>>
>> --- [begin]
>> First, definition of the relevant variables:
>>
>> pA = probability of Abiogenesis. More specifically, the probability,
>> given an earth-like planet, of life arising to a population and
>> robustness that, short of a cosmic catastrophe, it will not go
>> extinct for millions of years at least.
>> pP = probability of successful Pansperia. That is, the probability
>> that a single panspermia attempt on an earth-like planet will
>> result in life as described above.
>> pT = probability of Technological capability. Specifically, the
>> probability that, given life as described above, it will evolve
>> and develop a race technically capable of doing panspermia.
>> pS = probability, given the technical capability, that a race will
>> in fact attempt at least one panspermia seeding.
>

> Here is one flaw: You are assuming pA and pS are independent variables

> in your equations below. They are not. If pA is high, pS is low, and
> vice versa. Here is how Crick and Orgel put it:
>

> It seems unlikely that we would deliberately
> send terrestrial organisms to planets
> that we believed might already be inhabited.
> However, in view of the precarious situation
> on Earth, we might well be tempted to infect
> other planets if we became convinced that
> we were alone in the galaxy (Universe).
> ...
> The hypothetical senders on another planet
> may have been able to prove that they were
> likely to be alone, and to remain so, or they
> may have reached this conclusion mistakenly.
> In either case, if they resembled us
> psychologically, their motivation for polluting
> the galaxy would be strong, if they believed
> that all or even the great majority of
> inhabitable planets could be given life by
> Directed Panspermia.

[snip]

Count up the the conditional clauses in those paragraph to understand
the number of entities Crick and Orgel have added to the mix.

Mitchell Coffey

[pnyikos]

On Jan 18, 1:06 am, Mitchell Coffey <mitchelldotcof...@gmail.com>
wrote:

And now, Mitchell, you hint at other properties of earth without
spelling them out. That's already a big step forward from where Paul
left us.

> >>> The condition has no bearing on the fundamental question: if a planet
> >>> has life, what are the odds that this life arose by abiogenesis on
> >>> that planet versus its arising by panspermia?
>
> >> That is NOT the question you asked, nor is it the one to
> >> which I responded.
>
> > Well, duh. What you are responding to  NOW is the really fundamental
> > question.  See my next comment.
>
> >> You wrote;
>
> >>    "GIVEN that abiogenesis took place, what is the probability that
> >>     it took place on earth?"

Paul took this sentence in isolation from its context, which was to
try and assess the probability that life on earth arose from
abiogenesis here, as opposed to panspermia of organisms that arose via
abiogenesis elsewhere.

> > The really fundamental question has
>
> > "on *any* given planet on which life exists"
>
> > in place of "on earth".
>
> > The earth is simply an example of such a planet.  The fact that WE
> > don't know of any other such planet is irrelevant to the issue of
> > whether life on earth is the result of earthly abiogenesis, or
> > panspermia.
>
> Nonsense:

What you say next has no bearing on what I wrote in this last
paragraph you are quoting. Instead, it is relevant to what I said
about having to mention extra properties of the earth which set it
apart from the average planet on which life exists.

And so, your word "Nonsense" is itself nonsensically used.

> we know that life is possible on Earth, and that it was
> possible on Earth for life to evolve to include intelligent beings,

Yes, this is a big difference from what might be the typical planet on
which life exists. And this is what brings the odds against earthy
abiogenesis up, but how far up?

I talked about the factor involved in the thread about expanding the
Drake equation and the thread about the stages and benchmarks in the
evolution of life from prokaryotes to ourselves. In the first thread,
I fished for guesses about the probabilities but got no takers except
-- partially -- Mark Isaak.

Apparently people here are a lot more reticent about their guesses
than Carl Sagan was in _Cosmos_.

In the second thread, I talked about the factors that might make one
step in the evolution easier or harder than other steps. Again, very
little feedback -- whereas Sagan was quite expressive about the
thinking behind his guesses in _Cosmos_.

Judging from an earlier post of yours to this thread, you seem to
think of Sagan's _Cosmos_, except where it explains known scientific
facts, as no better than science fiction. Correct?

I would have guessed that people here think a lot more highly of Carl
Sagan than that.

Anyway, I've said often enough that I think the odds in favor of
directed seeding of earth vs. abiogenesis on earth are between about 3
- 1 and about 30 - 1. If I thought evolution from prokaryotes to an
intelligent species was a near sure thing, I would put the odds close
to a million to 1.

> and
> that on Earth conditions are such that wealthy industrial civilizations
> capable of space travel are possible.

If it weren't for that difference, I'd put the odds more in the 10 - 1
to 100 -1 range.

> We know this is possible on Earth.

Yup. All taken into account.

> You need to demonstrate that the probabilities that these may happen
> elsewhere are high enough to make DP probable.

I'll make a stab at it in Section E, which probably won't be ready
until some time next month. I have lots else on my plate, not all of
it having to do with Usenet, not by a long shot. One of them is my
department's annual High School Math Contest at the end of this month,
talked about here.

http://www.math.sc.edu/mathcomm/

There are links to detailed information on the last one and this
upcoming one. I have been in charge of the written test for both of
those, coordinating a very creative subcommittee.

> >> I point out again that the answer to this is strongly
> >> influenced by the fact that we DO have life on earth.
>
> > Well, duh again: if there were no life on earth, the whole question of
> > whether life on earth is due to abiogenesis or directed panspermia
> > would become MEANINGLESS.
>
> [snip]
>
> You should discuss this with our resident Bayesian.

Can you figure out what Gans's point was? Was it anything more than
the kindergarten-level observation that since there is life on earth,
that raises the probability of abiogenesis here on earth from 0 to
something respectable?

[pnyikos]

Mitchell is replying here to a post I canceled, but what I put in its
place was too technical, so I'm glad of the chance to return to that
earlier one.

On Jan 18, 1:49áam, Mitchell Coffey <mitchelldotcof...@gmail.com>
wrote:

> On 1/17/2013 5:18 PM, pnyikos wrote:

> > On Jan 17, 4:32 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
> >> On 1/16/13 10:03 AM, pnyikos wrote:
>

> >>> á á á á C: Connections with abiogenesis and intelligent design

>
> >>> C1: Does the ease or difficulty of abiogenesis have an effect on the
> >>> directed panspermia hypothesis?
>

> >>> Yes, but only on its probability, not the actual statement. á[...]

>
> >> This contradicts the calculations I made last year.
>
> > No, it only contradicts a conclusion you drew from them, after failing
> > to note an important point.
>
> >> Here's a large section of that post again:
>
> >> --- [begin]
> >> First, definition of the relevant variables:
>

> >> pA = probability of Abiogenesis. áMore specifically, the probability,
> >> á á ágiven an earth-like planet, of life arising to a population and
> >> á á árobustness that, short of a cosmic catastrophe, it will not go
> >> á á áextinct for millions of years at least.
> >> pP = probability of successful Pansperia. áThat is, the probability
> >> á á áthat a single panspermia attempt on an earth-like planet will
> >> á á áresult in life as described above.
> >> pT = probability of Technological capability. áSpecifically, the
> >> á á áprobability that, given life as described above, it will evolve
> >> á á áand develop a race technically capable of doing panspermia.

> >> pS = probability, given the technical capability, that a race will

> >> á á áin fact attempt at least one panspermia seeding.

>
> > Here is one flaw: You are assuming pA and pS are independent variables

> > in your equations below. áThey are not. áIf pA is high, pS is low, and
> > vice versa.

Here are those equations again, preceded by two numbers that go into
them

N = expected number of panspermia attempts by a race which is
attempting
panspermia. By definition, N >= 1.
U = number of earth-like planets in the universe.

Thus, analogous to the Drake equation, we have

Number of planets alive by abiogenesis =
La = U * pA
Number of planets alive by pansperia =
Lp = U * pA * pT * pS * N * pP
Probability that a planet's life arose by panspermia = Lp / (Lp + La)

My point was that if pA is very low, then both pS and N will be much
higher than if pA is high. In the first case, the fraction Lp / (Lp
+ La) will be much smaller than in the second case.

Mark failed to look at the effect of varying pA, and so erroneously
concluded that it had no effect on the fraction.

>>áHere is how Crick and Orgel put it:
>
> > á áIt seems unlikely that we would deliberately
> > á ásend terrestrial organisms to planets
> > á áthat we believed might already be inhabited.
> > á áHowever, in view of the precarious situation
> > á áon Earth, we might well be tempted to infect
> > á áother planets if we became convinced that
> > á áwe were alone in the galaxy (Universe).
> > ...
> > á áThe áhypothetical senders on another planet
> > á ámay have been able to prove that they were
> > á álikely to be alone, and to remain so, or they
> > á ámay have reached this conclusion mistakenly.
> > á áIn either case, if they resembled us
> > á ápsychologically, their motivation for polluting
> > á áthe galaxy would be strong, if they believed
> > á áthat all or even the great majority of
> > á áinhabitable planets could be given life by
> > á áDirected Panspermia.

>
> [snip]
>
> Count up the the conditional clauses in those paragraph to understand
> the number of entities Crick and Orgel have added to the mix.

Sure. If they weren't there, my estmate for Lp / (Lp + La) would be
something like 99/100 instead of being in the .75 to .97 range as it
is now. As to why the difference isn't more radical...

"if they believed" is just a question of them having attained to our
level of technology, and their access to hardy prokaryotes.

"if they resembled us psychologically" is somewhat misleadingly
worded. All it takes is for them to decide that for a planet to have
life is far better than for it not to have life.

Peter Nyikos

[pnyikos]

I was going to post Section D ("Delivery Systems") this week, but this
morning I chanced across the January issue of _National Geographic_ on
the Dept. of Math coffee table, and it talks about some of the same
things I've planned to talk about.

So I'll think carefully this weekend about how what I've written so
far should be reworded in the light of that article. I'm only post
the first question and answer today. It already takes into account
some things in that National Geographic article.

D1: What sorts of spacecraft could panspermists use to seed planets
1,000 light years away?

Two possible kinds are described in the 125th anniversary special
issue (January 2013) of National Geographic. The first is called
"Nuclear Pulse" and the second is called "Nuclear Fusion". Two other
kinds do not seem feasible as answers to D1. One, annihilation of
antimatter as the propulsion system, is well beyond our capabilities
and may be impossible to use as the primary means of propulsion. The
other, solar sails, is too slow.

Systems employing Nuclear Pulse and Nuclear Fusion were described long
ago with the help of multi-year projects, one by the US Air Force, and
one by the British Interplanetary Society. Each achieves a speed on
the order of magnitude of one-tenth of the speed of light. Neither
poses any serious scientific problems, only technological ones.

The first, Project Orion, does not seem to call for anything in
advance of our current level of technology. It uses thousands of
atomic or hydrogen bombs, exploded a safe distance behind the
spaceship, to propel the ship forward in a series of manageable jolts.
The brunt of the explosions is borne by a thick, hemispherical "pusher
plate" at the rear of the ship, and giant shock absorbers connect the
plate to the main body of the ship.

A detailed analysis of the methods, and costs, of a *manned* Project
Orion interstellar probe is to be found in the following article by
Freeman J. Dyson:

"Interstellar Transport," Physics Today, October 1968, pp. 41-45.

Unmanned probes, suitable for carrying only prokaryotes, could be much
smaller and less costly.

The second, Project Daedalus, is of a more advanced design. It
consists of a spaceship slightly larger than the Orion spaceship,
containing millions of pellets of a mixture of deuterium and helium-3,
exploded in a "combustion chamber" in a nuclear fusion reaction. The
fusion is triggered using electron beams of a high intensity -- but
perhaps not significantly higher than those currently available; some
of these have been around since 1958:

http://en.wikipedia.org/wiki/Electron_beam_welding


An esthetically pleasing, accessible place to start reading about
Daedalus is the various webpages of:

http://www.bisbos.com/space_n_daedalus.html

The concept of an auxiliary project, Icarus, is under development.
One of its functions would be to "mine" gas giants for Helium-3. See:

http://www.bisbos.com/space_n_icarus_fuel.html

The National Geographic article makes no mention of Helium-3, only
deuterium, so it is small wonder that one of its "Cons" for Nuclear
Fusion [page 76] is that "fusion reactors don't really work yet."

The Wikipedia entry on Project Daedalus is short but also
informative. The one on Orion is longer but unfocused.

[Paul J Gans]

pnyikos <nyi...@bellsouth.net> wrote:

>> >No, I just didn't say everything I could have said at that point. ?See

>> >below for the rest.


>> >>?You left out one
>> >> major condition, namely the only planet we know that does
>> >> have life is earth.

>This statement of yours says nothing special about the earth itself
>except that we happen to live on it. So the analysis I gave below is
>airtight--unless you can bring in other properties of earth that may
>make it necessary to modify it.


>> >The condition has no bearing on the fundamental question: if a planet
>> >has life, what are the odds that this life arose by abiogenesis on
>> >that planet versus its arising by panspermia?
>>
>> That is NOT the question you asked, nor is it the one to
>> which I responded.

>Well, duh. What you are responding to NOW is the really fundamental
>question. See my next comment.
>> You wrote;
>>

>> ? "GIVEN that abiogenesis took place, what is the probability that
>> ? ?it took place on earth?"

>The really fundamental question has

>"on *any* given planet on which life exists"

>in place of "on earth".

>The earth is simply an example of such a planet. The fact that WE
>don't know of any other such planet is irrelevant to the issue of
>whether life on earth is the result of earthly abiogenesis, or
>panspermia.

That is horse manure. The question being discussed here is not
about any planet. It is about the statement you made, now
quoted twice above. Deal with it and stop trying to duck
the issue.

And that issue is: GIVEN that abiogenesis took place, what is
the probabilty that it took place on earth? And the answer
to that question has to deal with the fact that there is life
here on earth.

This is now the second go-round on this. Stop trying to change
the subject.

[Paul J Gans]

pnyikos <nyi...@bellsouth.net> wrote:
>On Jan 18, 1:06?am, Mitchell Coffey <mitchelldotcof...@gmail.com>

>wrote:
>> On 1/17/2013 10:22 PM, pnyikos wrote:
>> > On Jan 17, 9:40 pm, Paul J Gans <gan...@panix.com> wrote:
>> >> pnyikos <nyik...@bellsouth.net> wrote:
>> >>> On Jan 17, 7:18?pm, Paul J Gans <gan...@panix.com> wrote:
>> >>>> pnyikos <nyik...@bellsouth.net> wrote:
>> >>>>> On Jan 17, 3:20?pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
>> >>>>>> On 1/16/13 12:02 PM, pnyikos wrote:

[snipped for sanity]

>> >>>>>>> And with perhaps billions of planets with
>> >>>>>>> good conditions for preserving life once it is established, the
>> >>>>>>> probability of the first is microscopic compared to that for the
>> >>>>>>> second.
>> >>>>> However, these probabilities are part of a red herring. ?Barring
>> >>>>> supernatural creation, we KNOW abiogenesis took place somewhere, and
>> >>>>> almost surely somewhere in our galaxy. The probability of directed
>> >>>>> panspermia is a conditional one: GIVEN that abiogenesis took place,
>> >>>>> what is the probability that it took place on earth?
>>
>> >>>> What you have above is a red herring.
>>
>> > You ignored what I said here, Paul:
>>

>> >>> No, I just didn't say everything I could have said at that point. ?See

>> >>> below for the rest.
>>
>> >>>> ?You left out one
>> >>>> major condition, namely the only planet we know that does
>> >>>> have life is earth.
>>
>> > This statement of yours says nothing special about the earth itself

>> > except that we happen to live on it. ?So the analysis I gave below is

>> > airtight--unless you can bring in other properties of earth that may
>> > make it necessary to modify it.

>And now, Mitchell, you hint at other properties of earth without
>spelling them out. That's already a big step forward from where Paul
>left us.

I left you dangling at the end of a rope of your own construction.
You constructed your statement (the one that beings with "GIVEN")
in such a way as to push the reader toward the response you want.
And you did that by leaving out the most important fact of all.

An honest statement would have been: GIVEN that abiogenesis
took place AND GIVEN that there is life on earth, what is the
probabilty that abiogenesis took place on earth?

That's a very different question and one for which you need an
answer that the probability is near zero. Without that your
entire hypothesis collapses.

But if you wish to continue to dangle, please do so.

>> >>> The condition has no bearing on the fundamental question: if a planet
>> >>> has life, what are the odds that this life arose by abiogenesis on
>> >>> that planet versus its arising by panspermia?
>>
>> >> That is NOT the question you asked, nor is it the one to
>> >> which I responded.
>>

>> > Well, duh. What you are responding to ?NOW is the really fundamental
>> > question. ?See my next comment.
>>
>> >> You wrote;
>>
>> >> ? ?"GIVEN that abiogenesis took place, what is the probability that
>> >> ? ? it took place on earth?"

>Paul took this sentence in isolation from its context, which was to
>try and assess the probability that life on earth arose from
>abiogenesis here, as opposed to panspermia of organisms that arose via
>abiogenesis elsewhere.

Nope. Read what I wrote above and please stop trying to change
the subject.

[rest deleted for clarity]

[Mark Isaak]

I refer mainly to the timing issue: The evidence is, life appeared on
earth pretty much as soon as it was possible for life to appear on
earth. Panspermia gives no reason to expect first life at any
particular time within the first 3 billion years. The probabilities
thus strongly favor abiogenesis. (Albeit it is "strong" only relative
to other panspermia arguments. I would estimate this argument by itself
puts the odds about 5:1 in favor of earth-based abiogenesis, as opposed
to other arguments which skew the odds on the order of 1.001:1 either way.)

I know you have seen this argument before. That you do not remember it
says a lot about the quality of your work.

>>>> Getting back to parsimony, a theory in which life arose abiogenetically
>>>> is more parsimonious than a theory in which life arose abiogentically,
>>>> did some complicated evolving, and was shot across the stars.
>>
>>> Only if you take the myopic view. Crick and Orgel hypothesized a
>>> massive project, which could easily mean -- assuming abiogenesis is a
>>> once-in-a-galaxy event -- that planets with life on them are
>>> overwhelmingly the product of directed paspermia. See the very end of
>>> the answer to A7.
>>
>> See that word "assuming" up there? As soon as you introduce it,
>> parsimony leaves by another door.
>
> Huh? Do you think it is more parsimonious to assume that abiogenesis
> occurs very frequently?

I think it is more parsimonious to make fewer assumptions. Each
assumption reduces parsimony.

>> Ockham's razor says (slightly paraphrased), "Do not multiply entities
>> without necessity."
>
>> Even you can see that you are multiplying entities.
>
> The main alternative is to assume that we are the first intelligent
> species to evolve in the whole galaxy, or at least that the first one
> evolved after life on earth began. How reasonable do you think that
> is?

Huh? The alternative is to assume that the life from which we evolved
began on earth. I think that is extremely reasonable. The rest of the
galaxy does not enter into it.

[Mark Isaak]

> that we believed might already be inhabited. [...]

Fair enough. But I must point out that your statement, "If pA is high,
pS is low" is also an assumption. Whether or not "we" would
deliberately seed inhabited planets is irrelevant, since we are not the
agents in question.

>> N = expected number of panspermia attempts by a race which is attempting
>> panspermia. By definition, N >= 1.
>
> And again, if pA is very small, N can be expected to be very large,
> and vice versa.

You can expect that. Others, including me, might not. I expect N is
dependent solely on the amount of disposable income which the
civilization has.

> The reasoning is similar to that above. Note that
> Crick and Orgel say "polluting the galaxy" and not just "polluting one
> or more planets."

If you look at the history of human colonization, polluting seems to be
the norm. I can see how one would not want it, but I don't know why one
would not expect it.

>> U = number of earth-like planets in the universe.
>
>> Thus, analogous to the Drake equation, we have
>
>> Number of planets alive by abiogenesis =
>> La = U * pA
>> Number of planets alive by pansperia =
>> Lp = U * pA * pT * pS * N * pP
>
> If pA is low, S is much more likely than if pA is high. The upshot is
> that p(A n S) is not the same as pA*pS, if one takes pS without
> reference to how high or low pA is. So the equation breaks down.
>
>> Probability that a planet's life arose by panspermia = Lp / (Lp + La)
>
> ...and that could be close to one (1) if pS and pN are large and pA is
> small, or close to 0 (zero) if pA is large and pS and N are small.

And that, I would say, is the bottom line: The probability of life from
panspermia is between 0 and 1. Beyond that is speculation.

[Mitchell Coffey]

On 1/18/2013 10:16 AM, pnyikos wrote:
> Mitchell is replying here to a post I canceled, but what I put in its
> place was too technical, so I'm glad of the chance to return to that
> earlier one.
>

> On Jan 18, 1:49 am, Mitchell Coffey <mitchelldotcof...@gmail.com>

> wrote:
>> On 1/17/2013 5:18 PM, pnyikos wrote:
>
>>> On Jan 17, 4:32 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
>>>> On 1/16/13 10:03 AM, pnyikos wrote:
>>
>>>>> C: Connections with abiogenesis and intelligent design
>>
>>>>> C1: Does the ease or difficulty of abiogenesis have an effect on the
>>>>> directed panspermia hypothesis?
>>

>>>>> Yes, but only on its probability, not the actual statement. [...]

>>
>>>> This contradicts the calculations I made last year.
>>
>>> No, it only contradicts a conclusion you drew from them, after failing
>>> to note an important point.
>>
>>>> Here's a large section of that post again:
>>
>>>> --- [begin]
>>>> First, definition of the relevant variables:
>>

>>>> pA = probability of Abiogenesis. More specifically, the probability,

>>>> given an earth-like planet, of life arising to a population and

>>>> robustness that, short of a cosmic catastrophe, it will not go

>>>> extinct for millions of years at least.

>>>> pP = probability of successful Pansperia. That is, the probability

>>>> that a single panspermia attempt on an earth-like planet will

>>>> result in life as described above.

>>>> pT = probability of Technological capability. Specifically, the

>>>> probability that, given life as described above, it will evolve

>>>> and develop a race technically capable of doing panspermia.
>>>> pS = probability, given the technical capability, that a race will

>>>> in fact attempt at least one panspermia seeding.
>>
>>> Here is one flaw: You are assuming pA and pS are independent variables

>>> in your equations below. They are not. If pA is high, pS is low, and

>>> vice versa.
>
> Here are those equations again, preceded by two numbers that go into
> them
>
> N = expected number of panspermia attempts by a race which is
> attempting panspermia. By definition, N >= 1.
>
> U = number of earth-like planets in the universe.
>
> Thus, analogous to the Drake equation, we have
>
> Number of planets alive by abiogenesis =
> La = U * pA
> Number of planets alive by pansperia =
> Lp = U * pA * pT * pS * N * pP
> Probability that a planet's life arose by panspermia = Lp / (Lp + La)
>
> My point was that if pA is very low, then both pS and N will be much
> higher than if pA is high. In the first case, the fraction Lp / (Lp
> + La) will be much smaller than in the second case.
>
> Mark failed to look at the effect of varying pA, and so erroneously
> concluded that it had no effect on the fraction.

True, Mark did not think of that point, and your analysis is valuable,
but it isn't definitive. For instance, note that your use of "pA" might
be better considered as "pAp," the probability of abiogenesis as
perceived by putative panspermists. Seen this way, it is yet another
entity. I suspect your point would be swamped by other issues regarding
the panspermists' motivations. See below, for one.

>>> Here is how Crick and Orgel put it:
>>

>>> It seems unlikely that we would deliberately

>>> send terrestrial organisms to planets

>>> that we believed might already be inhabited.

>>> However, in view of the precarious situation

>>> on Earth, we might well be tempted to infect

>>> other planets if we became convinced that

>>> we were alone in the galaxy (Universe).
>>> ...

>>> The hypothetical senders on another planet

>>> may have been able to prove that they were

>>> likely to be alone, and to remain so, or they

>>> may have reached this conclusion mistakenly.

>>> In either case, if they resembled us

>>> psychologically, their motivation for polluting

>>> the galaxy would be strong, if they believed

>>> that all or even the great majority of

>>> inhabitable planets could be given life by

>>> Directed Panspermia.
>>
>> [snip]
>>
>> Count up the the conditional clauses in those paragraph to understand
>> the number of entities Crick and Orgel have added to the mix.
>
> Sure. If they weren't there, my estmate for Lp / (Lp + La) would be
> something like 99/100 instead of being in the .75 to .97 range as it
> is now. As to why the difference isn't more radical...

I look forward to seeing the full calculations. I mean that seriously;
please don't interpret it as sarcasm.

> "if they believed" is just a question of them having attained to our
> level of technology, and their access to hardy prokaryotes.

They may have intended it to mean that, but a literal reading is more
accurate. What is the probability that the panspermists would believe
that "all or even the great majority of inhabitable planets could be
given life by" DP? Certainly the mere fact that they've attained our
level of technology and have access to appropriate prokaryotes

> "if they resembled us psychologically" is somewhat misleadingly
> worded. All it takes is for them to decide that for a planet to have
> life is far better than for it not to have life.

I don't see why that is particularly more probable. Besides, in addition
to deciding "that for a planet to have life is far better than for it
not to have life" they must decide that they care that other planets are
not thusly "better off" and that it is worth the necessary diversion of
resources, and that they continue to be so minded for the duration of
the project.

Regarding Crick and Orgel comment, above, about the conditions wherein
the panspermists' "motivation for polluting the galaxy would be strong."
The hidden assumption here is that the human motivation for imperialism,
colonization, exploration, literal pollution (?), etc. is a matter of
human nature, rather than having strong elements relating to economic
gain. Surely this is not the case. Note also, though, that probabilities
based on the nature of intelligent beings are likely difficult to
estimate with precision.

Mitchell Coffey

[Mitchell Coffey]

I've discussed them a bit in a post after the one you're responding to.
I'll note that it's also far from "air tight" for additional reasons,
unrelated to the properties of the Earth. But one or three things at at
time.

>>>>> The condition has no bearing on the fundamental question: if a planet
>>>>> has life, what are the odds that this life arose by abiogenesis on
>>>>> that planet versus its arising by panspermia?
>>
>>>> That is NOT the question you asked, nor is it the one to
>>>> which I responded.
>>
>>> Well, duh. What you are responding to NOW is the really fundamental
>>> question. See my next comment.
>>
>>>> You wrote;
>>
>>>> "GIVEN that abiogenesis took place, what is the probability that
>>>> it took place on earth?"
>
> Paul took this sentence in isolation from its context, which was to
> try and assess the probability that life on earth arose from
> abiogenesis here, as opposed to panspermia of organisms that arose via
> abiogenesis elsewhere.

Well I didn't.

>>> The really fundamental question has
>>> "on *any* given planet on which life exists"
>>> in place of "on earth".
>>
>>> The earth is simply an example of such a planet. The fact that WE
>>> don't know of any other such planet is irrelevant to the issue of
>>> whether life on earth is the result of earthly abiogenesis, or
>>> panspermia.
>>
>> Nonsense:
>
> What you say next has no bearing on what I wrote in this last
> paragraph you are quoting. Instead, it is relevant to what I said
> about having to mention extra properties of the earth which set it
> apart from the average planet on which life exists.

No, it's relevant to both. I intended it in response to you sentence
beginning "The fact that WE...".

> And so, your word "Nonsense" is itself nonsensically used.
>
>> we know that life is possible on Earth, and that it was
>> possible on Earth for life to evolve to include intelligent beings,
>
> Yes, this is a big difference from what might be the typical planet on
> which life exists. And this is what brings the odds against earthy
> abiogenesis up, but how far up?

How in Heavens name does the fact that we only know of life and advanced
civilizations on one planet *decrease* the probability that the life on
that planet originated on that planet?

I shall conjecture that most planets on which abiogenesis occurred and
led to viable life it would not evolve into intelligent life; that many
or most planets on which intelligent life arose did not for any
sufficient length of time, if ever, develop sufficiently advanced
civilization and technology; that most that did develop sufficiently
advanced civilization and technology, never decided on a DP project; and
that many or most that did, did not carry it through sufficiently long.
(You may dispute my mosts and manys, but these are indisputable
contingencies that require additional agencies.)

My point being, we do know one and only one planet in which all of these
things have happened, except a decision to undertake a DP project. It is
an heroic effort to assert that if these things hadn't happened on
Earth, abiogenisis is more likely to have happened here.

> I talked about the factor involved in the thread about expanding the
> Drake equation and the thread about the stages and benchmarks in the
> evolution of life from prokaryotes to ourselves. In the first thread,
> I fished for guesses about the probabilities but got no takers except
> -- partially -- Mark Isaak.
>
> Apparently people here are a lot more reticent about their guesses
> than Carl Sagan was in _Cosmos_.

[snip, riff on Sagan]

I don't care. I didn't watch most of the show, didn't read the book and
have a mixed opinion of Sagan. More importantly, if Sagan's charm,
appealing voice and endearing mannerisms allowed him to get away with
choosing numbers because, darn it!, they just felt right to him, it
doesn't make it a valid scientific methodology when you do it. Neither
would it's methodological validity improve if we vile claque of Howlers,
base as we are, maddened by our anti-Nykios ideology, hypocritically
allowed our love-interest Sagan to get away with it billions and
billions of times, yet clamp down on your ass. Hypocrisy is rife in this
veil of tears.

>> and
>> that on Earth conditions are such that wealthy industrial civilizations
>> capable of space travel are possible.
>
> If it weren't for that difference, I'd put the odds more in the 10 - 1
> to 100 -1 range.

Goody for you. I will look at your calculations with interest.

>> We know this is possible on Earth.
>
> Yup. All taken into account.

Are you intentionally looking to drive us mad with anticipation?!

>> You need to demonstrate that the probabilities that these may happen
>> elsewhere are high enough to make DP probable.
>
> I'll make a stab at it in Section E, which probably won't be ready
> until some time next month. I have lots else on my plate, not all of
> it having to do with Usenet, not by a long shot. One of them is my
> department's annual High School Math Contest at the end of this month,
> talked about here.

Good. A simple "I don't have the time just yet" would have sufficed.
Actually, the High School math contest is enduring as your perennial
tangents go, but... Why?

> http://www.math.sc.edu/mathcomm/
>
> There are links to detailed information on the last one and this
> upcoming one. I have been in charge of the written test for both of
> those, coordinating a very creative subcommittee.

Cool.

>>>> I point out again that the answer to this is strongly
>>>> influenced by the fact that we DO have life on earth.
>>
>>> Well, duh again: if there were no life on earth, the whole question of
>>> whether life on earth is due to abiogenesis or directed panspermia
>>> would become MEANINGLESS.
>>
>> [snip]
>>
>> You should discuss this with our resident Bayesian.
>
> Can you figure out what Gans's point was? Was it anything more than
> the kindergarten-level observation that since there is life on earth,
> that raises the probability of abiogenesis here on earth from 0 to
> something respectable?

Yes, I know what Paul meant. And, no, it's more like, since there is
life and civilization on Earth, it lowers the probability of abiogenesis
in the direction of irrelevant.

I directed you to Wilkins. Seeking him out, bow before him, put a twenty
in his cup, and he will probably still not respond.

Mitchell Coffey

[Paul J Gans]

pnyikos <nyi...@bellsouth.net> wrote:

>> >No, I just didn't say everything I could have said at that point. ?See

>> >below for the rest.


>> >>?You left out one
>> >> major condition, namely the only planet we know that does
>> >> have life is earth.

>This statement of yours says nothing special about the earth itself
>except that we happen to live on it. So the analysis I gave below is
>airtight--unless you can bring in other properties of earth that may
>make it necessary to modify it.

Your analysis is wrong. You cannot escape the question. The fact
is that life exists here on earth. You cannot talk about panspermy
without talking about that.

And of course you duck talking about your own question, because
the answer is devastating for your thesis. Thus you keep insisting
that the point lies somewhere else. It does not. It lies right
there.

>> >The condition has no bearing on the fundamental question: if a planet
>> >has life, what are the odds that this life arose by abiogenesis on
>> >that planet versus its arising by panspermia?
>>
>> That is NOT the question you asked, nor is it the one to
>> which I responded.

>Well, duh. What you are responding to NOW is the really fundamental
>question. See my next comment.

>> You wrote;
>>

>> ? "GIVEN that abiogenesis took place, what is the probability that
>> ? ?it took place on earth?"

>The really fundamental question has

>"on *any* given planet on which life exists"

>in place of "on earth".

No Peter, you cannot change the question to suit yourself. Other
planets are of no interest here. As the Bayesians would say, the
prior cannot be neglected. There IS life on earth and it came
either from elsewhere or is indigeneous. Deal with it.

>The earth is simply an example of such a planet. The fact that WE
>don't know of any other such planet is irrelevant to the issue of
>whether life on earth is the result of earthly abiogenesis, or
>panspermia.

>> I point out again that the answer to this is strongly
>> influenced by the fact that we DO have life on earth.

>Well, duh again: if there were no life on earth, the whole question of
>whether life on earth is due to abiogenesis or directed panspermia
>would become MEANINGLESS.

Exactly, so please don't try to get out of dealing with the
question.

>> >Our earth satisfies the "if" clause, and we move on to the rest of the
>> >question as applied to earth.
>> >> That changes the odds dramatically.
>> >On the contrary, whatever the odds are, the case of earth is one
>> >application of the odds, which are unaffected by a given application
>> >thereof.

>[snip unsupported accusation, and sequel]

[John S. Wilkins]

Mitchell Coffey <mitchell...@gmail.com> wrote:

> I directed you to Wilkins. Seeking him out, bow before him, put a twenty
> in his cup, and he will probably still not respond.

He'd have to Bayes before me.
--
John S. Wilkins, Associate, Philosophy, University of Sydney
Honorary Fellow, University of Melbourne
- http://evolvingthoughts.net

[Ron O]

On Jan 18, 6:19�pm, j...@wilkins.id.au (John S. Wilkins) wrote:

> Mitchell Coffey <mitchelldotcof...@gmail.com> wrote:
> > I directed you to Wilkins. Seeking him out, bow before him, put a twenty
> > in his cup, and he will probably still not respond.
>
> He'd have to Bayes before me.

You can choke on those leaves if you don't take them out of the pot.

[John S. Wilkins]

Ron O <roki...@cox.net> wrote:

> On Jan 18, 6:19 pm, j...@wilkins.id.au (John S. Wilkins) wrote:
> > Mitchell Coffey <mitchelldotcof...@gmail.com> wrote:
> > > I directed you to Wilkins. Seeking him out, bow before him, put a twenty
> > > in his cup, and he will probably still not respond.
> >
> > He'd have to Bayes before me.
>
> You can choke on those leaves if you don't take them out of the pot.
>

You know this a priori? How frequently is it observed to happen?

[Paul J Gans]

John S. Wilkins <jo...@wilkins.id.au> wrote:
>Mitchell Coffey <mitchell...@gmail.com> wrote:

>> I directed you to Wilkins. Seeking him out, bow before him, put a twenty
>> in his cup, and he will probably still not respond.

>He'd have to Bayes before me.

He who would serve Wilkins must OBayes him?

[Walter Bushell]

In article <kdcidl$mu$1...@dont-email.me>,

Mitchell Coffey <mitchell...@gmail.com> wrote:

> Yes, I know what Paul meant. And, no, it's more like, since there is
> life and civilization on Earth, it lowers the probability of abiogenesis
> in the direction of irrelevant.

I dispute your assertion that there is civilization on Earth. Mayhap
in Australia, but they (as I have gathered from Wilkins postings about
the political scene) are losing it.

--
This space unintentionally left blank.

[Paul J Gans]

John S. Wilkins <jo...@wilkins.id.au> wrote:

>Ron O <roki...@cox.net> wrote:

>> On Jan 18, 6:19 pm, j...@wilkins.id.au (John S. Wilkins) wrote:
>> > Mitchell Coffey <mitchelldotcof...@gmail.com> wrote:
>> > > I directed you to Wilkins. Seeking him out, bow before him, put a twenty
>> > > in his cup, and he will probably still not respond.
>> >
>> > He'd have to Bayes before me.
>>
>> You can choke on those leaves if you don't take them out of the pot.
>>
>You know this a priori? How frequently is it observed to happen?

In the US it is right up there with gun and auto deaths.
Those bay leaves are downright dangerous.

But you'll find no statistics. I suspect a coverup.

[Ron O]

On Jan 18, 7:24�pm, Paul J Gans <gan...@panix.com> wrote:
> John S. Wilkins <j...@wilkins.id.au> wrote:

>
> >Ron O <rokim...@cox.net> wrote:
> >> On Jan 18, 6:19 pm, j...@wilkins.id.au (John S. Wilkins) wrote:
> >> > Mitchell Coffey <mitchelldotcof...@gmail.com> wrote:
> >> > > I directed you to Wilkins. Seeking him out, bow before him, put a twenty
> >> > > in his cup, and he will probably still not respond.
>
> >> > He'd have to Bayes before me.
>
> >> You can choke on those leaves if you don't take them out of the pot.
>
> >You know this a priori? How frequently is it observed to happen?
>
> In the US it is right up there with gun and auto deaths.
> Those bay leaves are downright dangerous.
>
> But you'll find no statistics. �I suspect a coverup.

There must be a coverup. It ranks up there with "You'll go blind...."

Don't Aussie mothers make their kids search the pot for the bay leaves
before you serve the stew, or is it just salt and boil it until it is
done like in the UK?

Ron Okimoto

[Michael Siemon]

In article <proto-772A4C....@news.panix.com>,

New Zealand; there is hope as long as there is a New Zealand...

[Mitchell Coffey]

On 1/18/2013 7:19 PM, John S. Wilkins wrote:
> Mitchell Coffey <mitchell...@gmail.com> wrote:
>
>> I directed you to Wilkins. Seeking him out, bow before him, put a twenty
>> in his cup, and he will probably still not respond.
>
> He'd have to Bayes before me.
>

I've been waiting for you for Bayes on end.

Mitchell

[Walter Bushell]

In article
<mlsiemon-F39397...@c-61-68-245-199.per.connect.net.au>,

That is my other dream place of relocation, however it's also the site
of a super volcano. However so is North America.

[jillery]

I didn't know you spoke Pig Latin.

[Mitchell Coffey]

I was referring to Canada.

Mitchell

[jillery]

On Fri, 18 Jan 2013 22:44:20 -0500, Walter Bushell <pr...@panix.com>

wrote:

>In article
><mlsiemon-F39397...@c-61-68-245-199.per.connect.net.au>,
> Michael Siemon <mlsi...@sonic.net> wrote:
>
>> In article <proto-772A4C....@news.panix.com>,
>> Walter Bushell <pr...@panix.com> wrote:
>>
>> > In article <kdcidl$mu$1...@dont-email.me>,
>> > Mitchell Coffey <mitchell...@gmail.com> wrote:
>> >
>> > > Yes, I know what Paul meant. And, no, it's more like, since there is
>> > > life and civilization on Earth, it lowers the probability of abiogenesis
>> > > in the direction of irrelevant.
>> >
>> > I dispute your assertion that there is civilization on Earth. Mayhap
>> > in Australia, but they (as I have gathered from Wilkins postings about
>> > the political scene) are losing it.
>>
>> New Zealand; there is hope as long as there is a New Zealand...
>
>That is my other dream place of relocation, however it's also the site
>of a super volcano. However so is North America.

Yeppers. There is no place on Earth that is safe from all natural
disasters. The best you can do is pick your poison and take your
chances.

[Walter Bushell]

In article <31ckf89cv2do3k97s...@4ax.com>,

jillery <69jp...@gmail.com> wrote:

> >That is my other dream place of relocation, however it's also the site
> >of a super volcano. However so is North America.
>
>
> Yeppers. There is no place on Earth that is safe from all natural
> disasters. The best you can do is pick your poison and take your
> chances.

I suppose. But North America has Republicans, so I think it is not for
choice.

[Walter Bushell]

In article <kddaub$qof$1...@dont-email.me>,

Mitchell Coffey <mitchell...@gmail.com> wrote:

> On 1/18/2013 8:23 PM, Walter Bushell wrote:
> > In article <kdcidl$mu$1...@dont-email.me>,
> > Mitchell Coffey <mitchell...@gmail.com> wrote:
> >
> >> Yes, I know what Paul meant. And, no, it's more like, since there is
> >> life and civilization on Earth, it lowers the probability of abiogenesis
> >> in the direction of irrelevant.
> >
> > I dispute your assertion that there is civilization on Earth. Mayhap
> > in Australia, but they (as I have gathered from Wilkins postings about
> > the political scene) are losing it.
>
> I was referring to Canada.
>
> Mitchell

Some truth to that but the climate. And then there is being close to
America. Currently America allows Canada a lot of freedom, but the
operative word is "allows".

[Mitchell Coffey]

Just so long as the majority doesn't start speaking in French. As things
are, we can understand what they're up to.

Mitchell Coffey

[Michael Siemon]

In article <kddfj3$qof$7...@dont-email.me>,

eh? what makes you think so... we are separated by a "common" language.
They are "understandable" to us only when, as now, they have a batshit
crazy "Conservative" government which almost resembles our own lunacy.

[John S. Wilkins]

Never judge the civilisation of a nation by its politicians (some Kiwis
these days are as bad as anything in the UK, although nothing civil is
as bad as anything in the US).

One should judge the civilisation of a nation by the time they permit
politicians to remain in office.

[Paul J Gans]

Oink, oink.

[Paul J Gans]

That's life!

[Paul J Gans]

But they still have a better health system and better health outcomes
than we do.

[Walter Bushell]

In article <1kwy9gw.1hlyfg1ijlgfjN%jo...@wilkins.id.au>,

jo...@wilkins.id.au (John S. Wilkins) wrote:

> Michael Siemon <mlsi...@sonic.net> wrote:
>
> > In article <proto-772A4C....@news.panix.com>,
> > Walter Bushell <pr...@panix.com> wrote:
> >
> > > In article <kdcidl$mu$1...@dont-email.me>,
> > > Mitchell Coffey <mitchell...@gmail.com> wrote:
> > >
> > > > Yes, I know what Paul meant. And, no, it's more like, since there is
> > > > life and civilization on Earth, it lowers the probability of abiogenesis
> > > > in the direction of irrelevant.
> > >
> > > I dispute your assertion that there is civilization on Earth. Mayhap
> > > in Australia, but they (as I have gathered from Wilkins postings about
> > > the political scene) are losing it.
> >
> > New Zealand; there is hope as long as there is a New Zealand...
>
> Never judge the civilisation of a nation by its politicians (some Kiwis
> these days are as bad as anything in the UK, although nothing civil is
> as bad as anything in the US).
>
> One should judge the civilisation of a nation by the time they permit
> politicians to remain in office.

That still puts America in a bad light. Once elected to Congress, the
job is almost secure as we have gerrymandered the election districts
into safe seats. Republican do have to fear a challenger from the
right in the primary.

But whoever is elected turns into a politician.

[Michael Siemon]

In article <kden8p$ki4$6...@reader1.panix.com>,

Paul J Gans <gan...@panix.com> wrote:

Because they have _not_ had decades and decades of batshit crazy
"conservative" governments... :-)

[Paul J Gans]

I suspect it all comes down to lousy education and a religious
system that pushes folks to believe all sorts of crazy stuff.

Most civilized nations have curricula set nationally so that it
is harder for the batshits to change it. On the other hand now
that Turkey has banned the selling of any book dealing with
evolution, the problems of centralized education are obvious.

Nevertheless remember the "we don't need to teach algebra"
bruhaha of a couple of months ago. That one was mainly left
wing. That sort of thing is what encourages innumerancy
among our leaders.

[John S. Wilkins]

Walter Bushell <pr...@panix.com> wrote:

> In article <1kwy9gw.1hlyfg1ijlgfjN%jo...@wilkins.id.au>,
> jo...@wilkins.id.au (John S. Wilkins) wrote:
>
> > Michael Siemon <mlsi...@sonic.net> wrote:
> >
> > > In article <proto-772A4C....@news.panix.com>,
> > > Walter Bushell <pr...@panix.com> wrote:
> > >
> > > > In article <kdcidl$mu$1...@dont-email.me>,
> > > > Mitchell Coffey <mitchell...@gmail.com> wrote:
> > > >
> > > > > Yes, I know what Paul meant. And, no, it's more like, since there
> > > > > is life and civilization on Earth, it lowers the probability of
> > > > > abiogenesis in the direction of irrelevant.
> > > >
> > > > I dispute your assertion that there is civilization on Earth. Mayhap
> > > > in Australia, but they (as I have gathered from Wilkins postings
> > > > about the political scene) are losing it.
> > >
> > > New Zealand; there is hope as long as there is a New Zealand...
> >
> > Never judge the civilisation of a nation by its politicians (some Kiwis
> > these days are as bad as anything in the UK, although nothing civil is
> > as bad as anything in the US).
> >
> > One should judge the civilisation of a nation by the time they permit
> > politicians to remain in office.
>
> That still puts America in a bad light. Once elected to Congress, the
> job is almost secure as we have gerrymandered the election districts
> into safe seats. Republican do have to fear a challenger from the
> right in the primary.

That was my point. Also, most democracies turn into plutocracies very
quickly. The rise of a political class happens immediately. We now have
fourth generation Labor political families in Australia!

>
> But whoever is elected turns into a politician.

And ensures their children also become politicians.

[Walter Bushell]

In article <kdes0u$2su$1...@reader1.panix.com>,

The thing that pushes innumeracy amongst our leaders is that
advocating a rational resource allocation by politician will result in
that politician not being reelected.

[Free Lunch]

On Sat, 19 Jan 2013 19:10:35 -0500, Walter Bushell <pr...@panix.com>
wrote in talk.origins:

Only because we have one entire party and half of the other one
committed to telling lies to the electorate. If Paul Ryan, Eric Cantor
and any pair of Democrats who you think are equally untrustworthy were
whipped for each lie they told, the lies would diminish immediately.

[Walter Bushell]

In article <8udmf8liqnvqpj2l5...@4ax.com>,

But as long as the electorate will not elect people who will not lie
to them, liars will predominate and more or less every politician must
lie.

[jillery]

On Sat, 19 Jan 2013 19:26:22 +0000 (UTC), Paul J Gans

If so, it's an illustration of the dichotomy of centralized authority.
A benign dictator is a wonderful thing. A despotic dictator, not so
much.

[J. J. Lodder J. J. Lodder]

John S. Wilkins <jo...@wilkins.id.au> wrote:

All this is far worse in pseudo-democracies
in which minorities are artificially inflated into majorities
by having a district system.
(Anglo-Saxonia, and also France)

The Netherlands for example, with fully proportional representation,
with no artifical threshold, [1]
there is not a single political dynasty in national policics.

It is also notable that inhabitants the USA etc.
tend to turn the obvuous evils inherent in their political systems
into supposedly ineviatble laws of human nature.

Jan

[1] In fact there is a negative threshold.
Personal votes are reinforced.

[Nick Keighley]

On Jan 17, 9:59 pm, pnyikos <nyik...@bellsouth.net> wrote:
> On Jan 17, 2:53 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
>
>
>
>
>
>
>
>
>
> > On 1/16/13 10:12 AM, pnyikos wrote:
> > > On Jan 15, 9:12 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
> > >> On 1/15/13 12:18 PM, pnyikos wrote:
>
> > >>> [...]
> > >>> B3. But doesn't Ockham's Razor strongly favor life abiotically
> > >>> produced on earth rather than by seeding by space aliens?
>
> > >>> Ockham's Razor decrees only that the most parsimonious explanation be
> > >>> given after ALL evidence has been scrutinized, and what little
> > >>> evidence there is [see the answer to A7], is on the side of directed
> > >>> panspermia.
>
> > >> A7 speaks to probability, not parsimony. And the little evidence does
> > >> not weigh to the side of dirPan because you left out A8, the evidence
> > >> *against* (which far outweighs the evidence in favor).
>
> > > You are looking in the wrong place. Section A is historical. It is
> > > in Section B that I deal with objections that you don't mention here,
> > > except for a simplistic view of the Razor that you give below.
>
> What Section A does is mention the evidence Crick and Orgel dealt
> with, and in that original Icarus article, it's all for DP, unless one
> accepts  the hypothesis that abiogenesis is quite common.
>
> > Whatever. It still seems to me that evidence for and evidence against
> > should be adjacent, but it's your FAQ.
> > > Do you regularly play with the cards held this close to your chest?
>
> > You mean, do I not repeat myself endlessly?
>
> Don't be daft.  You talk about the evidence against "far outweighing"
> the evidence for, but fail to even mention any of that "outweighing"
> evidence, except as noted below.
>
> > No, I don't. Besides, it
> > is your job to look for and keep track of the evidence against directed
> > panspermia.
>
> I've looked for it in the many threads that have been devoted to the
> subject, and I think I've given most of the ones I've found in Section
> B, except for those dealing with spaceflight, which will be in Section
> D.
>
> > >> Getting back to parsimony, a theory in which life arose abiogenetically
> > >> is more parsimonious than a theory in which life arose abiogentically,
> > >> did some complicated evolving, and was shot across the stars.
>
> > > Only if you take the myopic view. Crick and Orgel hypothesized a
> > > massive project, which could easily mean -- assuming abiogenesis is a
> > > once-in-a-galaxy event -- that planets with life on them are
> > > overwhelmingly the product of directed paspermia. See the very end of
> > > the answer to A7.
>
> > See that word "assuming" up there? As soon as you introduce it,
> > parsimony leaves by another door.
>
> Huh?  Do you think it is more parsimonious to assume that abiogenesis
> occurs very frequently?
>
> [snip]
>
> > Ockham's razor says (slightly paraphrased), "Do not multiply entities
> > without necessity."
> > Even you can see that you are multiplying entities.
>
> The main alternative is to assume that we are the first intelligent
> species to evolve in the whole galaxy, or at least that the first one
> evolved after life on earth began.  How reasonable do you think that
> is?

surely the most parsimonious explanation is that life has evolved
several times in the galaxy. We simply haven't observed any other
examples because of the distances involved.

[Paul J Gans]

Yup. But I insist that the problem lies with the voters. After
all, democracy is that form of government where the people get
what they ask for.

[Paul J Gans]

I truly thing that some of them have repeated their stories so
often that they've gotten to believe them.

[Paul J Gans]

Exactly.

On the other hand some centralized authority is necessary.

[Walter Bushell]

In article <kdhjv1$pl2$4...@reader1.panix.com>,

Paul J Gans <gan...@panix.com> wrote:

> Free Lunch <lu...@nofreelunch.us> wrote:
> >On Sat, 19 Jan 2013 19:10:35 -0500, Walter Bushell <pr...@panix.com>
> >wrote in talk.origins:
>
> >>In article <kdes0u$2su$1...@reader1.panix.com>,
> >> Paul J Gans <gan...@panix.com> wrote:
> >>
> >>> Nevertheless remember the "we don't need to teach algebra"
> >>> bruhaha of a couple of months ago. That one was mainly left
> >>> wing. That sort of thing is what encourages innumerancy
> >>> among our leaders.
> >>>
> >>
> >>The thing that pushes innumeracy amongst our leaders is that
> >>advocating a rational resource allocation by politician will result in
> >>that politician not being reelected.
>
> >Only because we have one entire party and half of the other one
> >committed to telling lies to the electorate. If Paul Ryan, Eric Cantor
> >and any pair of Democrats who you think are equally untrustworthy were
> >whipped for each lie they told, the lies would diminish immediately.
>
> I truly thing that some of them have repeated their stories so
> often that they've gotten to believe them.

The situation is far more complex than that. Parts of the person's
personality can have different beliefs than others. For most people,
unity of the personality is a confabulation.

[Walter Bushell]

In article
<55235e17-10b2-4a01...@f19g2000vbv.googlegroups.com>,

The most parsimonious explanation is that life evolved only here, and
besides it has the advantage of being testable. OTOH, perhaps life
started on Mars and spread to Earth, which will be testable in the
near future, perhaps.

[Mitchell Coffey]

As I've always said, Pro-life, my ass!

Mitchell Coffey

[Mitchell Coffey]

There are only three or four political dynasties in the United States,
and only the Kennedys and Bushes are nationally significant.

You miss an important part of what makes the US a "pseudo-democracy."
More important than the district system is that the upper-house isn't
elected even nominally proportionally. California, with 36 million
people, has 2 Senators, just like eight states with a million or fewer,
and 41 states in between.

Mitchell Coffey

[Paul J Gans]

I'm of two minds about this.

[Paul J Gans]

Walter Bushell <pr...@panix.com> wrote:
>In article
><55235e17-10b2-4a01...@f19g2000vbv.googlegroups.com>,
> Nick Keighley <nick_keigh...@hotmail.com> wrote:

>> On Jan 17, 9:59?pm, pnyikos <nyik...@bellsouth.net> wrote:
>> > On Jan 17, 2:53 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> > > On 1/16/13 10:12 AM, pnyikos wrote:
>> > > > On Jan 15, 9:12 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
>> > > >> On 1/15/13 12:18 PM, pnyikos wrote:
>> >
>> > > >>> [...]
>> > > >>> B3. But doesn't Ockham's Razor strongly favor life abiotically
>> > > >>> produced on earth rather than by seeding by space aliens?
>> >
>> > > >>> Ockham's Razor decrees only that the most parsimonious explanation be
>> > > >>> given after ALL evidence has been scrutinized, and what little
>> > > >>> evidence there is [see the answer to A7], is on the side of directed
>> > > >>> panspermia.
>> >
>> > > >> A7 speaks to probability, not parsimony. And the little evidence does
>> > > >> not weigh to the side of dirPan because you left out A8, the evidence
>> > > >> *against* (which far outweighs the evidence in favor).
>> >
>> > > > You are looking in the wrong place. Section A is historical. It is
>> > > > in Section B that I deal with objections that you don't mention here,
>> > > > except for a simplistic view of the Razor that you give below.
>> >
>> > What Section A does is mention the evidence Crick and Orgel dealt
>> > with, and in that original Icarus article, it's all for DP, unless one

>> > accepts ?the hypothesis that abiogenesis is quite common.

>> >
>> > > Whatever. It still seems to me that evidence for and evidence against
>> > > should be adjacent, but it's your FAQ.
>> > > > Do you regularly play with the cards held this close to your chest?
>> >
>> > > You mean, do I not repeat myself endlessly?
>> >

>> > Don't be daft. ?You talk about the evidence against "far outweighing"

>> > the evidence for, but fail to even mention any of that "outweighing"
>> > evidence, except as noted below.
>> >
>> > > No, I don't. Besides, it
>> > > is your job to look for and keep track of the evidence against directed
>> > > panspermia.
>> >
>> > I've looked for it in the many threads that have been devoted to the
>> > subject, and I think I've given most of the ones I've found in Section
>> > B, except for those dealing with spaceflight, which will be in Section
>> > D.
>> >
>> > > >> Getting back to parsimony, a theory in which life arose abiogenetically
>> > > >> is more parsimonious than a theory in which life arose abiogentically,
>> > > >> did some complicated evolving, and was shot across the stars.
>> >
>> > > > Only if you take the myopic view. Crick and Orgel hypothesized a
>> > > > massive project, which could easily mean -- assuming abiogenesis is a
>> > > > once-in-a-galaxy event -- that planets with life on them are
>> > > > overwhelmingly the product of directed paspermia. See the very end of
>> > > > the answer to A7.
>> >
>> > > See that word "assuming" up there? As soon as you introduce it,
>> > > parsimony leaves by another door.
>> >

>> > Huh? ?Do you think it is more parsimonious to assume that abiogenesis

>> > occurs very frequently?
>> >
>> > [snip]
>> >
>> > > Ockham's razor says (slightly paraphrased), "Do not multiply entities
>> > > without necessity."
>> > > Even you can see that you are multiplying entities.
>> >
>> > The main alternative is to assume that we are the first intelligent
>> > species to evolve in the whole galaxy, or at least that the first one

>> > evolved after life on earth began. ?How reasonable do you think that

>> > is?
>>
>> surely the most parsimonious explanation is that life has evolved
>> several times in the galaxy. We simply haven't observed any other
>> examples because of the distances involved.

>The most parsimonious explanation is that life evolved only here, and
>besides it has the advantage of being testable. OTOH, perhaps life
>started on Mars and spread to Earth, which will be testable in the
>near future, perhaps.

Doubtful, at least in my mind. The problem is that light output
from the sun early on was notably smaller than it is today.
Several ingenous mechanisms have to be invoked to explain why
the earth was not a snowball back then, the most recent being
an article in Science claiming that nitrogen-hydrogen colliions
would produce broadening of absorption lines to induce global
warming of enough magnitude to keep the earth from totally
freezing.

Mars would have been even colder.

Two points: there seems to be no evidence that the earth was
ever totally frozen. The other is that if the nitrogen-hydrogen
hypothesis is true, we would then gain something of a handle on
the atmosphere of the early earth.

[James Beck]

On Jan 20, 4:27 am, nos...@de-ster.demon.nl (J. J. Lodder) (J. J.
Lodder) wrote:

> John S. Wilkins <j...@wilkins.id.au> wrote:
>
>
>
>
>
>
>
>
>
> > Walter Bushell <pr...@panix.com> wrote:
>

> > > In article <1kwy9gw.1hlyfg1ijlgfjN%j...@wilkins.id.au>,
> > >  j...@wilkins.id.au (John S. Wilkins) wrote:
>
> > > > Michael Siemon <mlsie...@sonic.net> wrote:
>
> > > > > In article <proto-772A4C.20230518012...@news.panix.com>,
> > > > >  Walter Bushell <pr...@panix.com> wrote:
>
> > > > > > In article <kdcidl$m...@dont-email.me>,

This system of sham democracy was perfected by the ancient Romans and
has been gradually watered down since. Under the one-tribe-one-vote
rule, with 2% of the population assigned to the 17 aristocratic tribes
and the rest assigned to the 4 urban tribes, no one should be
surprised that only 2% of Rome's citizens bothered to vote.

The US is familiar with the two-percent problem. Over the recent
period they gerrymandered districts, with the support of political
appointees to the judicial bench. At the moment they're pushing for an
expansion of district voting. It seems that Romans don't learn unless
they burn.

> The Netherlands for example, with fully proportional representation,
> with no artifical threshold, [1]
> there is not a single political dynasty in national policics.
>
> It is also notable that inhabitants the USA etc.
> tend to turn the obvuous evils inherent in their political systems
> into supposedly ineviatble laws of human nature.

> [1] In fact there is a negative threshold.
> Personal votes are reinforced.

You have this backward. They say that all aspects of human political
systems inevitably reflect human nature because it is tautological.
Difficulties arise when people attempt to describe what human nature
must (or must not) have been by examining outcomes top-down. You
appear to be as guilty of that as those you criticize.

[jillery]

On Mon, 21 Jan 2013 00:23:52 +0000 (UTC), Paul J Gans

As long as you don't let them argue about it with each other...

[jillery]

Of course, if you meant that the Earth was never totally frozen to its
core, that's something else altogether. But IIUC there is evidence
that the Earth's surface was covered over by ice, from pole-to-pole:

<http://en.wikipedia.org/wiki/Snowball_earth>

and not just once but several times.

Desertphile recently posted a link to a BBC documentary on the
subject:

<http://www.youtube.com/watch?v=ydLNrTzMIgc>

If you don't like to watch these things, much of what the video talks
about is included in the Wikipedia bibliography.

I'm not sure how a Snowball Earth makes homegrown abiogenesis more (or
less) likely.

[Bill]

On Jan 19, 1:46 am, Mark Isaak <eci...@curioustax.onomy.net> wrote:

> On 1/17/13 1:59 PM, pnyikos wrote:
>
>
>
>
>
>
>
>
>
> > On Jan 17, 2:53 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
> >> On 1/16/13 10:12 AM, pnyikos wrote:
>
> >>> On Jan 15, 9:12 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
> >>>> On 1/15/13 12:18 PM, pnyikos wrote:
>
> >>>>> [...]
> >>>>> B3. But doesn't Ockham's Razor strongly favor life abiotically
> >>>>> produced on earth rather than by seeding by space aliens?
>
> >>>>> Ockham's Razor decrees only that the most parsimonious explanation be
> >>>>> given after ALL evidence has been scrutinized, and what little
> >>>>> evidence there is [see the answer to A7], is on the side of directed
> >>>>> panspermia.
>
> >>>> A7 speaks to probability, not parsimony.  And the little evidence does
> >>>> not weigh to the side of dirPan because you left out A8, the evidence
> >>>> *against* (which far outweighs the evidence in favor).
>
> >>> You are looking in the wrong place.  Section A is historical.  It is
> >>> in Section B that I deal with objections that  you don't mention here,
> >>> except for a simplistic view of the Razor that you give below.
>
> > What Section A does is mention the evidence Crick and Orgel dealt
> > with, and in that original Icarus article, it's all for DP, unless one

> > accepts  the hypothesis that abiogenesis is quite common.

>
> >> Whatever.  It still seems to me that evidence for and evidence against
> >> should be adjacent, but it's your FAQ.
>
> >>> Do you regularly play with the cards held this close to your chest?
>
> >> You mean, do I not repeat myself endlessly?
>

> > Don't be daft.  You talk about the evidence against "far outweighing"

> > the evidence for, but fail to even mention any of that "outweighing"
> > evidence, except as noted below.
>
> >>   No, I don't.  Besides, it
> >> is your job to look for and keep track of the evidence against directed
> >> panspermia.
>
> > I've looked for it in the many threads that have been devoted to the
> > subject, and I think I've given most of the ones I've found in Section
> > B, except for those dealing with spaceflight, which will be in Section
> > D.
>

> I refer mainly to the timing issue:  The evidence is, life appeared on
> earth pretty much as soon as it was possible for life to appear on
> earth.  Panspermia gives no reason to expect first life at any
> particular time within the first 3 billion years.  The probabilities
> thus strongly favor abiogenesis.  (Albeit it is "strong" only relative
> to other panspermia arguments.  I would estimate this argument by itself
> puts the odds about 5:1 in favor of earth-based abiogenesis, as opposed
> to other arguments which skew the odds on the order of 1.001:1 either way.)
>
> I know you have seen this argument before.  That you do not remember it
> says a lot about the quality of your work.

>
> >>>> Getting back to parsimony, a theory in which life arose abiogenetically
> >>>> is more parsimonious than a theory in which life arose abiogentically,
> >>>> did some complicated evolving, and was shot across the stars.
>
> >>> Only if you take the myopic view.  Crick and Orgel hypothesized a
> >>> massive project, which could easily mean -- assuming abiogenesis is a
> >>> once-in-a-galaxy event  -- that planets with life on them are
> >>> overwhelmingly the product of directed paspermia.  See the very end of
> >>> the answer to A7.
>
> >> See that word "assuming" up there?  As soon as you introduce it,
> >> parsimony leaves by another door.
>

> > Huh?  Do you think it is more parsimonious to assume that abiogenesis
> > occurs very frequently?
>
> I think it is more parsimonious to make fewer assumptions.  Each
> assumption reduces parsimony.

>
> >> Ockham's razor says (slightly paraphrased), "Do not multiply entities
> >> without necessity."
>
> >>   Even you can see that you are multiplying entities.
>
> > The main alternative is to assume that we are the first intelligent
> > species to evolve in the whole galaxy, or at least that the first one

> > evolved after life on earth began.  How reasonable do you think that
> > is?
>
> Huh?  The alternative is to assume that the life from which we evolved
> began on earth.  I think that is extremely reasonable.  The rest of the
> galaxy does not enter into it.
>
> --
> Mark Isaak          eciton (at) curioustaxonomy (dot) net
> "It is certain, from experience, that the smallest grain of natural
>   honesty and benevolence has more effect on men's conduct, than the most
>   pompous views suggested by theological theories and systems." - D. Hume

From the TalkOrigins front page:

The TalkOrigins Archive is a collection of articles and essays, most
of which have appeared in talk.origins at one time or another. The
primary reason for this archive's existence is ***to provide
mainstream scientific responses*** to the many frequently asked
questions (FAQs) that appear in the talk.origins newsgroup and the
frequently rebutted assertions of those advocating intelligent design
or other creationist pseudosciences.

Very little about the Directed Panspermia FAQ as proposed strikes me
as "mainstream science," for many of the reasons you and others in the
thread bring up.

[Walter Bushell]

In article <kdi1qo$82u$2...@reader1.panix.com>,

You're lucky you can get it down to only two minds. Of course two
minds can have 7 opinions.

[pnyikos]

On Jan 20, 10:43 am, Nick Keighley <nick_keighley_nos...@hotmail.com>
wrote:

Mark Isaak gave an objection I'd temporarily forgotten about. On the
other hand, I hadn't given all the evidence against abiogenesis
either. Foremost among these is that we have no evidence of any
earthly self-replicators more primitive than the simplest free-living
prokaryotes -- already an incredibly sophisticated life form.

[Viruses are not self-replicators; they have to commandeer the whole
translation apparatus of a host cell; viroids aren't either: they need
host cells to supply them with nucleotides.]

I'll have more to say about this in direct reply to Mark. I hope you
can continue to follow this discussion.

> > > >> Getting back to parsimony, a theory in which life arose abiogenetically
> > > >> is more parsimonious than a theory in which life arose abiogentically,
> > > >> did some complicated evolving, and was shot across the stars.
>
> > > > Only if you take the myopic view. Crick and Orgel hypothesized a
> > > > massive project, which could easily mean -- assuming abiogenesis is a
> > > > once-in-a-galaxy event -- that planets with life on them are
> > > > overwhelmingly the product of directed paspermia. See the very end of
> > > > the answer to A7.
>
> > > See that word "assuming" up there? As soon as you introduce it,
> > > parsimony leaves by another door.
>
> > Huh?  Do you think it is more parsimonious to assume that abiogenesis
> > occurs very frequently?
>
> > [snip]
>
> > > Ockham's razor says (slightly paraphrased), "Do not multiply entities
> > > without necessity."
> > > Even you can see that you are multiplying entities.
>
> > The main alternative is to assume that we are the first intelligent
> > species to evolve in the whole galaxy, or at least that the first one
> > evolved after life on earth began.  How reasonable do you think that
> > is?
>
> surely the most parsimonious explanation is that life has evolved
> several times in the galaxy. We simply haven't observed any other
> examples because of the distances involved.

I don't see why that is the most parsimonious. You are multiplying
entities unnecessarily, if that slight paraphrasal of Mark's is taken
literally.

It may be the most reasonable, and most in line with a sophisticated
understanding of Ockham's Razor, but you need to explain why you think
that.

Peter Nyikos

[pnyikos]

On Jan 20, 8:14 pm, James Beck <jdbeck11...@gmail.com> wrote:

[snip unnecessary attribution lines]

> > > > > Michael Siemon <mlsie...@sonic.net> wrote:
>
> > > > > > In article <proto-772A4C.20230518012...@news.panix.com>,
> > > > > >  Walter Bushell <pr...@panix.com> wrote:
>
> > > > > > > In article <kdcidl$m...@dont-email.me>,
> > > > > > >  Mitchell Coffey <mitchelldotcof...@gmail.com> wrote:
>
> > > > > > > > Yes, I know what Paul meant. And, no, it's more like, since there
> > > > > > > > is life and civilization on Earth, it lowers the probability of
> > > > > > > > abiogenesis in the direction of irrelevant.
>

Mitchell got this backwards -- but then I got something similar
backwards, and will need to do damage control.

> > > > > > > I dispute your assertion that there is civilization on Earth. Mayhap
> > > > > > > in Australia, but they (as I have gathered from Wilkins postings
> > > > > > > about the political scene) are losing it.
>
> > > > > > New Zealand; there is hope as long as there is a New Zealand...

One of my favorite places. I've tried to go back there every two
years since 2000, but had to skip 2010. It was great to be back there
again last year.

[much off-topic discussion snipped]

> The US is familiar with the two-percent problem. Over the recent
> period they gerrymandered districts, with the support of political
> appointees to the judicial bench. At the moment they're pushing for an
> expansion of district voting. It seems that Romans don't learn unless
> they burn.

Nice to see you here, James. Hope you stick around for some on-topic
discussion.

Political philosophy may play a role in assessing how likely a
technological species is to undertake a directed panspermia project,
but I doubt that this particular topic is the best place to start.

Peter Nyikos

[pnyikos]

On Jan 21, 7:55�am, Bill <brogers31...@gmail.com> wrote:
> On Jan 19, 1:46�am, Mark Isaak <eci...@curioustax.onomy.net> wrote:

> > On 1/17/13 1:59 PM, pnyikos wrote:
>
> > > On Jan 17, 2:53 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
> > >> On 1/16/13 10:12 AM, pnyikos wrote:
>
> > >>> On Jan 15, 9:12 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:

[snip]

> > >>>> Getting back to parsimony, a theory in which life arose abiogenetically
> > >>>> is more parsimonious than a theory in which life arose abiogentically,
> > >>>> did some complicated evolving, and was shot across the stars.
>
> > >>> Only if you take the myopic view. �Crick and Orgel hypothesized a
> > >>> massive project, which could easily mean -- assuming abiogenesis is a
> > >>> once-in-a-galaxy event �-- that planets with life on them are
> > >>> overwhelmingly the product of directed paspermia. �See the very end of
> > >>> the answer to A7.
>
> > >> See that word "assuming" up there? �As soon as you introduce it,
> > >> parsimony leaves by another door.
>
> > > Huh? �Do you think it is more parsimonious to assume that abiogenesis
> > > occurs very frequently?
>
> > I think it is more parsimonious to make fewer assumptions. �Each
> > assumption reduces parsimony.

Mark is shaving too closely with the razor here. Abiogenesis may be
abundant in the galaxy, or it may be exceedingly rare, and, as Pogo's
friend Porky said about a closely related topic, "Either way, it's a
mighty sobering thought." [That's an allusion to the great Walt Kelly
comic strip "Pogo".]

An analysis which simply ignores this whole range of possibilities
risks losing out on some important insights as to how likely it is
that life on earth began with seeding of life that arose far away.

> > >> Ockham's razor says (slightly paraphrased), "Do not multiply entities
> > >> without necessity."
>
> > >> � Even you can see that you are multiplying entities.
>
> > > The main alternative is to assume that we are the first intelligent
> > > species to evolve in the whole galaxy, or at least that the first one
> > > evolved after life on earth began. �How reasonable do you think that
> > > is?
>
> > Huh? �The alternative is to assume that the life from which we evolved
> > began on earth.

Mark continues to shave too close. I was talking about the main
alternative to multiplying entities, in the general context how likely
(or unlikely) it is that life on earth began with seeding of life that
arose far away.

[more too-close shaving by Mark deleted]

> From the TalkOrigins front page:
>
> The TalkOrigins Archive is a collection of articles and essays, most
> of which have appeared in talk.origins at one time or another. The
> primary reason for this archive's existence is ***to provide
> mainstream scientific responses*** to the many frequently asked
> questions (FAQs) that appear in the talk.origins newsgroup and the
> frequently rebutted assertions of those advocating intelligent design
> or other creationist pseudosciences.
>
> Very little about the Directed Panspermia FAQ as proposed strikes me
> as "mainstream science," for many of the reasons you and others in the
> thread bring up.

My responses belong to mainstream science, and that is how I intend to
keep them. No flights of fancy about time travel, no highly
speculative means such as matter-antimatter annihilation and
interstellar ramjets, no talk of manned missions to other planetary
systems.

As you can see from my answer to D1, and to B8 [to which the answer
to D1 is very relevant], I stick close to what we already know and
what we are likely to be capable of in the next few centuries, barring
the collapse of civilization.

Only one person so far has claimed that civilization will collapse,
but his reason -- exploding population -- may be rapidly becoming
obsolete with the precipitous drop in the fertility rate, especially
in the developed countries.

Peter Nyikos
Professor, Dept. of Mathematics -- standard disclaimer--
University of South Carolina
http://www.math.sc.edu/~nyikos/
nyikos @ math.sc.edu

[pnyikos]

On Jan 20, 10:38 pm, jillery <69jpi...@gmail.com> wrote:
> On Mon, 21 Jan 2013 00:28:04 +0000 (UTC), Paul J Gans
>
>
>
>
>
>
>
>
>
> <gan...@panix.com> wrote:
> >Walter Bushell <pr...@panix.com> wrote:
> >>In article

> >><55235e17-10b2-4a01-afab-027f83c0b...@f19g2000vbv.googlegroups.com>,

> >> Nick Keighley <nick_keighley_nos...@hotmail.com> wrote:

> >>> surely the most parsimonious explanation is that life has evolved
> >>> several times in the galaxy. We simply haven't observed any other
> >>> examples because of the distances involved.

My reply to Nick, less than an hour ago, was similar to the one Walter
makes:

> >>The most parsimonious explanation is that life evolved only here, and
> >>besides it has the advantage of being testable. OTOH, perhaps life
> >>started on Mars and spread to Earth, which will be testable in the
> >>near future, perhaps.
>
> >Doubtful, at least in my mind.  The problem is that light output
> >from the sun early on was notably smaller than it is today.
> >Several ingenous mechanisms have to be invoked to explain why
> >the earth was not a snowball back then, the most recent being
> >an article in Science claiming that nitrogen-hydrogen colliions
> >would produce broadening of absorption lines to induce global
> >warming of enough magnitude to keep the earth from totally
> >freezing.

I don't see why ingenious mechanisms are needed. The earth may have
had much more in the way of greenhouse gases (especially carbon
dioxide) than it does now. Think of how much global warming there
would be if the 21% oxygen were all replaced by carbon dioxide!

The snowball earths can be blamed on the rise of cyanobacteria and
other kinds of bacteria, with the cyanobacteria doing that 21% bit in
reverse--only much more, since a lot of the oxygen they gave out as a
"waste product" went into oxidizing large quantities of dissolved
ferrous oxide.

The first url given by jillery below mentions this process, which
resulted in banded iron formations.

See also the following website:

http://www.damninteresting.com/how-bacteria-nearly-destroyed-all-life
the following url takes one to the same page:

http://www.damninteresting.com/?p=673

The main article has to do with the Huronian glaciation, back in the
Archaean, and it blames other kinds of bacteria for removing a lot of
the methane. However, in the many comments, carbon dioxide comes into
the discussion, along with lots of talk about global warming.

> >Mars would have been even colder.
>
> >Two points:  there seems to be no evidence that the earth was
> >ever totally frozen.

The evidence is ambiguous. More needs to be known.

> >The other is that if the nitrogen-hydrogen
> >hypothesis is true, we would then gain something of a handle on
> >the atmosphere of the early earth.
>
> Of course, if you meant that the Earth was never totally frozen to its
> core, that's something else altogether.  But IIUC there is evidence
> that the Earth's surface was covered over by ice, from pole-to-pole:
>
> <http://en.wikipedia.org/wiki/Snowball_earth>
>
> and not just once but several times.
>
> Desertphile recently posted a link to a BBC documentary on the
> subject:
>
> <http://www.youtube.com/watch?v=ydLNrTzMIgc>
>
> If you don't like to watch these things, much of what the video talks
> about is included in the Wikipedia bibliography.
>
> I'm not sure how a Snowball Earth makes homegrown abiogenesis more (or
> less) likely.

It has probably has nothing to do with it, because even the earliest
of them came about a billion years after the seeding event that I have
hypothesized.

[pnyikos]

On Jan 18, 1:46 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
> On 1/17/13 1:59 PM, pnyikos wrote:

>
> > On Jan 17, 2:53 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
> >> On 1/16/13 10:12 AM, pnyikos wrote:
>
> >>> On Jan 15, 9:12 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:

> >>>> On 1/15/13 12:18 PM, pnyikos wrote:
>
> >>>>> [...]
> >>>>> B3. But doesn't Ockham's Razor strongly favor life abiotically
> >>>>> produced on earth rather than by seeding by space aliens?
>
> >>>>> Ockham's Razor decrees only that the most parsimonious explanation be
> >>>>> given after ALL evidence has been scrutinized, and what little
> >>>>> evidence there is [see the answer to A7], is on the side of directed
> >>>>> panspermia.
>
> >>>> A7 speaks to probability, not parsimony.  And the little evidence does
> >>>> not weigh to the side of dirPan because you left out A8, the evidence
> >>>> *against* (which far outweighs the evidence in favor).
>
> >>> You are looking in the wrong place.  Section A is historical.  It is
> >>> in Section B that I deal with objections that  you don't mention here,
> >>> except for a simplistic view of the Razor that you give below.
>
> > What Section A does is mention the evidence Crick and Orgel dealt
> > with, and in that original Icarus article, it's all for DP, unless one
> > accepts  the hypothesis that abiogenesis is quite common.
>
> >> Whatever.  It still seems to me that evidence for and evidence against
> >> should be adjacent, but it's your FAQ.

Well, Section B was for "pointed questions", and those have to do with
evidence against. Maybe the final version of the FAQ will simply be
called "Some Pros and Cons."

> >>> Do you regularly play with the cards held this close to your chest?
>
> >> You mean, do I not repeat myself endlessly?
>
> > Don't be daft.  You talk about the evidence against "far outweighing"
> > the evidence for, but fail to even mention any of that "outweighing"
> > evidence, except as noted below.

What's more, I left out one big argument for panspermia, and against
earthly abiogenesis.
This is that we have no evidence of any efficient earthly self-

replicators more primitive than the simplest free-living prokaryotes
-- already an incredibly sophisticated life form.

You may argue that the efficient prokaryotes gobbled up everything
that preceded them, but I have to wonder why we don't even see any
simpler genetic codes than the standard one. Also, why no
microfossils suggesting more primitive forms?

We are discovering life deep within the earth, and one might think
that some relict organisms may still be found down there. In fact,
around 1996, there was some hope that "nanobes" which were found here
and there deep in the earth, might be just such a life form.

http://en.wikipedia.org/wiki/Nanobe

But if they are actual protobionts, one would think that this would
have been proven by now, and the story of earth life revolutionized
thereby. It is the stuff of which Nobel Prizes are given out.

Instead, here it is 16 years later, and the Wikipedia entry on it is
still very meager.

The situation of "nanobacteria" is similar: close to two decades of
research, and not much hope. One wag called them "the cold fusion of
microbiology":

http://en.wikipedia.org/wiki/Nanobacteria

> >>   No, I don't.  Besides, it
> >> is your job to look for and keep track of the evidence against directed
> >> panspermia.
>
> > I've looked for it in the many threads that have been devoted to the
> > subject, and I think I've given most of the ones I've found in Section
> > B, except for those dealing with spaceflight, which will be in Section
> > D.
>

> I refer mainly to the timing issue:  The evidence is, life appeared on
> earth pretty much as soon as it was possible for life to appear on
> earth.

"pretty much as soon" means "within a few hundred million years."

> Panspermia gives no reason to expect first life at any
> particular time within the first 3 billion years.

...or even later.

> The probabilities
> thus strongly favor abiogenesis.

You are leaving out a lot of analysis here. Once you weigh all the
pros and cons, I doubt that you'll get such a big number as you get
here:

> (Albeit it is "strong" only relative
> to other panspermia arguments.  I would estimate this argument by itself
> puts the odds about 5:1 in favor of earth-based abiogenesis, as opposed
> to other arguments which skew the odds on the order of 1.001:1 either way.)

I exposed the flaw in your main argument for the latter, in reply to
Mitchell Coffey. Care to see it?

> I know you have seen this argument before.  That you do not remember it
> says a lot about the quality of your work.

What you forget is that I replied that the knife cuts both ways, and
Howard Hershey's 1990's "manifesto" crowded this issue temporarily out
of my memory. Thanks for reminding me of it.

Hershey's "manifesto" was that the evidence seemed to point to
prokaryotes arising in a mere 100 million years, and that this was his
only reason FOR taking directed panspermia seriously: the jump from
prebiotic soup to prokaryotes is a huge one, and 100 milllion years
seems a very short time for it.

I've dealt with what you wrote later in my reply to Bill Rogers.

I know I am taking the risk of incurring your wrath for pointing you
to a post in reply to someone else, but the alternatives are not so
good either: (1) split my reply in two, which is even more likely to
incur your wrath.(2) incur the derision of Mitchell Coffey and Paul
Gans by just posting an url and not the whole post, and (3) repost
everything, thereby making this post considerably longer than it
already is....

Peter Nyikos

[pnyikos]

On Jan 18, 5:30 pm, Mitchell Coffey <mitchelldotcof...@gmail.com>
wrote:
> On 1/18/2013 9:58 AM, pnyikos wrote:

> > On Jan 18, 1:06 am, Mitchell Coffey <mitchelldotcof...@gmail.com>
> > wrote:
> >> On 1/17/2013 10:22 PM, pnyikos wrote:
>
> >>> On Jan 17, 9:40 pm, Paul J Gans <gan...@panix.com> wrote:

[Gans wrote earlier:]
> >>>>>> ?You left out one
> >>>>>> major condition, namely the only planet we know that does
> >>>>>> have life is earth.
>
> >>> This statement of yours says nothing special about the earth itself
> >>> except that we happen to live on it.  So the analysis I gave below is
> >>> airtight--unless you can bring in other properties of earth that may
> >>> make it necessary to modify it.
>
> > And now, Mitchell, you hint at other properties of earth without
> > spelling them out.  That's already a big step forward from where Paul
> > left us.
>
> I've discussed them a bit in a post after the one you're responding to.
> I'll note that it's also far from "air tight" for additional reasons,
> unrelated to the properties of the Earth. But one or three things at at
> time.

Fine.

> >>>>> The condition has no bearing on the fundamental question: if a planet
> >>>>> has life, what are the odds that this life arose by abiogenesis on
> >>>>> that planet versus its arising by panspermia?
>
> >>>> That is NOT the question you asked, nor is it the one to
> >>>> which I responded.
>
> >>> Well, duh. What you are responding to  NOW is the really fundamental
> >>> question.  See my next comment.
>
> >>>> You wrote;
>
> >>>>     "GIVEN that abiogenesis took place, what is the probability that
> >>>>      it took place on earth?"
>
> > Paul took this sentence in isolation from its context, which was to
> > try and assess the probability that life on earth arose from
> > abiogenesis here, as opposed to panspermia of organisms that arose via
> > abiogenesis elsewhere.
>
> Well I didn't.

Thanks.

> >>> The really fundamental question has
> >>> "on *any* given planet on which life exists"
> >>> in place of "on earth".
>
> >>> The earth is simply an example of such a planet.  The fact that WE
> >>> don't know of any other such planet is irrelevant to the issue of
> >>> whether life on earth is the result of earthly abiogenesis, or
> >>> panspermia.
>
> >> Nonsense:
>
> > What you say next has no bearing on what I wrote in this last
> > paragraph you are quoting.  Instead, it is relevant to what I said
> > about having to mention extra properties of the earth which set it
> > apart from the average planet on which life exists.
>
> No, it's relevant to both. I intended it in response to you sentence
> beginning "The fact that WE...".

You are focusing on the word "WE," and now I see your point.

> > And so, your word "Nonsense" is itself nonsensically used.

I take that back: your "Nonsense" was merely premature.

> >> we know that life is possible on Earth, and that it was
> >> possible on Earth for life to evolve to include intelligent beings,
>
> > Yes, this is a big difference from what might be the typical planet on
> > which life exists.  And this is what brings the odds against earthy
> > abiogenesis up, but how far up?

Oops, I meant "way down." Sort of like Gans saying "west" when he
meant "east" on another thread, and you own statement,

"since there is life and civilization on Earth,
it lowers the probability of abiogenesis in
the direction of irrelevant."

We all seem to be having senior moments these days. :-(

> How in Heavens name does the fact that we only know of life and advanced
> civilizations on one planet *decrease* the probability that the life on
> that planet originated on that planet?

It doesn't. Thanks for catching my error.

> I shall conjecture that most planets on which abiogenesis occurred and
> led to viable life it would not evolve into intelligent life;

I, also.

> that many
> or most planets on which intelligent life arose did not for any
> sufficient length of time, if ever, develop sufficiently advanced
> civilization and technology;

About 50-50 seems as good a guess as any. Agreed?

> that most that did develop sufficiently
> advanced civilization and technology, never decided on a DP project;

Agreed, but not "overwhelmingly most". I'd say about half that got as
far as us would go in for instrumental probes to thousands of
planetary systems. (Call that Technological Stage 2, ours being
Technological Stage 1).

And then comes the big unknown: what would they find? I think the
first Technological Stage 2 in our galaxy will find no life even after
searching thousands of otherwise very promising planets. Assuming
this...

> and
> that many or most that did, did not carry it through sufficiently long.

"Sufficiently long" is what I call Technological Stage 3; I give going
from TS2 to TS3 another 50-50 chance.

ON THE OTHER HAND, if abiogenesis is very common, I give a massive
panspermia project very low odds, and most of those would likely fail
in competition with existing life. Recall the following entry from
Section B:

B6. What if life is very common in our galaxy? What would that do to
the hypothesis of directed panspermia?

That would entirely depend on the origins of that life. If all
technological societies preceding ours were confronted with life in
the majority of suitable planets, I doubt that there would ever have
been a directed panspermia project.
================== end of entry

I'm not the pro-DP fanatic some people here seem to think I am. I
will abandon the hypothesis if faced with compelling arguments, and
one of those would be a compelling argument for the ease of developing
"life as we know it."

> (You may dispute my mosts and manys, but these are indisputable
> contingencies that require additional agencies.)

Yup.

Concluded in next post. I hope I was correct in remembering that it
was Mark Isaak, and not you, who lambasted me once for splitting my
replies. I do it mainly to keep the length of my replies down.

Peter Nyikos

[pnyikos]

On Jan 18, 5:30 pm, Mitchell Coffey <mitchelldotcof...@gmail.com>
wrote:
> On 1/18/2013 9:58 AM, pnyikos wrote:

> > On Jan 18, 1:06 am, Mitchell Coffey <mitchelldotcof...@gmail.com>
> > wrote:

Repeating a bit from the first reply, for continuity:

> >> we know that life is possible on Earth, and that it was
> >> possible on Earth for life to evolve to include intelligent beings,
>
> > Yes, this is a big difference from what might be the typical planet on
> > which life exists.

[snip list of things between a merely intelligent species and one
undertaking massive panspermia, discussed in first reply]

> > I talked about the factor involved in the thread about expanding the
> > Drake equation and the thread about the stages and benchmarks  in the
> > evolution of life from prokaryotes to ourselves.  In the first thread,
> > I fished for guesses about the probabilities but got no takers except
> > -- partially -- Mark Isaak.
>
> > Apparently people here are a lot more reticent about their guesses
> > than Carl Sagan was in _Cosmos_.
>
> [snip, riff on Sagan]
>
> I don't care. I didn't watch most of the show, didn't read the book and
> have a mixed opinion of Sagan. More importantly, if Sagan's charm,
> appealing voice and endearing mannerisms allowed him to get away with
> choosing numbers because, darn it!, they just felt right to him,

No, he was rather articulate in explaining why he chose those
numbers. Granted, other people looking at the same evidence have
chosen very different ones. But his choices were very much in the
mainstream of thinking about the Drake equation at the time he wrote
the book.

[snip]

> >> and
> >> that on Earth conditions are such that wealthy industrial civilizations
> >> capable of space travel are possible.
>
> > If it weren't for that difference, I'd put the odds more in the 10 - 1
> > to 100 -1 range.
>
> Goody for you. I will look at your calculations with interest.
>
> >> We know this is possible on Earth.
>
> > Yup.  All taken into account.
>
> Are you intentionally looking to drive us mad with anticipation?!

No, and that is why I wrote what I did below.

> >> You need to demonstrate that the probabilities that these may happen
> >> elsewhere are high enough to make DP probable.
>
> > I'll make a stab at it in Section E, which probably won't be ready
> > until some time next month.  I have lots else on my plate, not all of
> > it having to do with Usenet, not by a long shot.  One of them is my
> > department's annual High School Math Contest at the end of this month,
> > talked about here.
>
> Good. A simple "I don't have the time just yet" would have sufficed.

I was afraid that would not have gone over too well. I am not one of
the Village Elders of talk.origins, nor do I aspire to be.

> Actually, the High School math contest is enduring as your perennial
> tangents go, but... Why?

We full Professors are not exempt from service to the Department,
University, and Community, and this is for me a pleasant way of
providing such service.

> >http://www.math.sc.edu/mathcomm/
>
> > There are links to detailed information on the last one and this
> > upcoming one.  I have been in charge of the written test for both of
> > those, coordinating a very creative subcommittee.
>
> Cool.
>
> >>>> I point out again that the answer to this is strongly
> >>>> influenced by the fact that we DO have life on earth.
>
> >>> Well, duh again: if there were no life on earth, the whole question of
> >>> whether life on earth is due to abiogenesis or directed panspermia
> >>> would become MEANINGLESS.
>
> >> [snip]
>
> >> You should discuss this with our resident Bayesian.
>
> > Can you figure out what Gans's point was?  Was it anything more than
> > the kindergarten-level observation that since there is life on earth,
> > that raises the probability of abiogenesis here on earth from 0 to
> > something respectable?
>
> Yes, I know what Paul meant. And, no, it's more like, since there is

> life and civilization on Earth, it lowers the probability of abiogenesis
> in the direction of irrelevant.
>

> I directed you to Wilkins. Seeking him out, bow before him, put a twenty
> in his cup, and he will probably still not respond.

I saw John's flip response. I wonder whether he thinks Gans was just
clowning around.

If so, Gans has really been laying the clowning on thick this weekend,
starting early Friday afternoon.

Peter Nyikos

[Paul J Gans]

They do argue. That's where typos and brainos come from.

[Paul J Gans]

The same article in Science that talked about the nitrogen-hydrogen
business stated, with references, that there is no geological
evidence for "snowball earth". I can't cite the article as my
wife has made the issue disappear in her zeal to clean up the
debris I leave around the house, but an online search of the
Science site gives the abstract. See

http://www.sciencemag.org/content/339/6115/64

The actual article is paywalled unless your library has a subscription.

The first sentence of the abstract is:

"Understanding how Earth has sustained surface liquid water
throughout its history remains a key challenge, given that
the Sun???s luminosity was much lower in the pas."

So no snowball earth.

By the way, it is very hard to undestand how life could have
survived a complete snowballization of the earth's surface.

[Mark Isaak]

On 1/21/13 12:24 PM, pnyikos wrote:
> On Jan 18, 1:46 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
>> On 1/17/13 1:59 PM, pnyikos wrote:

> [...]

>
> What's more, I left out one big argument for panspermia, and against
> earthly abiogenesis.
> This is that we have no evidence of any efficient earthly self-
> replicators more primitive than the simplest free-living prokaryotes
> -- already an incredibly sophisticated life form.
>
> You may argue that the efficient prokaryotes gobbled up everything
> that preceded them, but I have to wonder why we don't even see any
> simpler genetic codes than the standard one.

The answer to that is obvious. Do you also wonder why Ford Motor
Company does not still sell Model-Ts?

> Also, why no microfossils suggesting more primitive forms?

What would you consider "more primitive" than a microscopic speck in a
rock? We have such fossils now, albeit folks dispute whether they are
fossils or not.

> We are discovering life deep within the earth, and one might think
> that some relict organisms may still be found down there.

I would think they would have to be quite highly evolved to adapt to the
extreme environment.

[snip re nanobes and nanobacteria, which are not relevant]

>>
>> I refer mainly to the timing issue: The evidence is, life appeared on
>> earth pretty much as soon as it was possible for life to appear on
>> earth.
>
> "pretty much as soon" means "within a few hundred million years."
>
>> Panspermia gives no reason to expect first life at any
>> particular time within the first 3 billion years.
>
> ...or even later.
>
>> The probabilities thus strongly favor abiogenesis.
>
> You are leaving out a lot of analysis here. Once you weigh all the
> pros and cons, I doubt that you'll get such a big number as you get
> here:
>
>> (Albeit it is "strong" only relative
>> to other panspermia arguments. I would estimate this argument by itself
>> puts the odds about 5:1 in favor of earth-based abiogenesis, as opposed
>> to other arguments which skew the odds on the order of 1.001:1 either way.)
>
> I exposed the flaw in your main argument for the latter, in reply to
> Mitchell Coffey. Care to see it?

If you don't care to summarize here, I must assume it is not worth
looking at.

> Hershey's "manifesto" was that the evidence seemed to point to
> prokaryotes arising in a mere 100 million years, and that this was his
> only reason FOR taking directed panspermia seriously: the jump from
> prebiotic soup to prokaryotes is a huge one, and 100 milllion years
> seems a very short time for it.

Yet another conclusion based not on data, but on the absence of it.
Such arguments are garbage, and I am exceedingly tired of seeing them.

[Mark Isaak]

On 1/21/13 11:15 AM, pnyikos wrote:
>> On Jan 19, 1:46 am, Mark Isaak <eci...@curioustax.onomy.net> wrote:
>>> On 1/17/13 1:59 PM, pnyikos wrote:

>> [...]

>>>> Huh? Do you think it is more parsimonious to assume that abiogenesis
>>>> occurs very frequently?
>>
>>> I think it is more parsimonious to make fewer assumptions. Each
>>> assumption reduces parsimony.
>
> Mark is shaving too closely with the razor here. Abiogenesis may be
> abundant in the galaxy, or it may be exceedingly rare, and, as Pogo's
> friend Porky said about a closely related topic, "Either way, it's a
> mighty sobering thought."
>

> An analysis which simply ignores this whole range of possibilities
> risks losing out on some important insights as to how likely it is
> that life on earth began with seeding of life that arose far away.

I do not believe you have yet said what your purpose is.

Do you want to show that directed panspermia is possible? You have done
that.

Do you want to show a science-fiction scenario with plausible DirPan?
Then you need to worry about probabilities scarcely at all and Ockham's
Razor not a bit. All you need to ensure is that you label the
speculation as speculation.

Do you want to show that evidence favors DirPan over earth-based
abiogenesis? Then you are simply wrong; there is not remotely enough
evidence. And, in lack of evidence, prudent and proper use of Ockham's
razor is important.

>>>>> Ockham's razor says (slightly paraphrased), "Do not multiply entities
>>>>> without necessity."
>>
>>>>> Even you can see that you are multiplying entities.
>>
>>>> The main alternative is to assume that we are the first intelligent
>>>> species to evolve in the whole galaxy, or at least that the first one
>>>> evolved after life on earth began. How reasonable do you think that
>>>> is?
>>
>>> Huh? The alternative is to assume that the life from which we evolved
>>> began on earth.
>
> Mark continues to shave too close. I was talking about the main
> alternative to multiplying entities, in the general context how likely
> (or unlikely) it is that life on earth began with seeding of life that
> arose far away.

If that is your context, then the alternative is to assume that the life

from which we evolved began on earth.

[Bob Berger]

In article <kdkfse$e8a$1...@dont-email.me>, Mark Isaak says...

>
>On 1/21/13 12:24 PM, pnyikos wrote:
>> On Jan 18, 1:46 pm, Mark Isaak <eci...@curioustax.onomy.net> wrote:
>>> On 1/17/13 1:59 PM, pnyikos wrote:
>> [...]
>>
>> What's more, I left out one big argument for panspermia, and against
>> earthly abiogenesis.
>> This is that we have no evidence of any efficient earthly self-
>> replicators more primitive than the simplest free-living prokaryotes
>> -- already an incredibly sophisticated life form.
>>
>> You may argue that the efficient prokaryotes gobbled up everything
>> that preceded them, but I have to wonder why we don't even see any
>> simpler genetic codes than the standard one.
>
>The answer to that is obvious. Do you also wonder why Ford Motor
>Company does not still sell Model-Ts?

While this is completely OT to this thread, yes I do. Given today's nostalgia
market, I'll bet they'd make a fortune. :-)

[Mitchell Coffey]

And exactly how do you know enough about the Throomians to suppose that
their population fertility dynamics work in someway similar to humans,
and that Throomians would face similar relevant conditions?

I'm fairly sure people have mentioned more than one possible cause of
the collapse of a civilization. In any case, there are other ways that
civilizations might collapse, and indeed have collapsed. These have
included economic decline, military defeat, political decline or
conquest, disease, climate change, resource depletion and *declining*
population. There have been several cases where the governments of
relatively advanced nation have rejected technological and economic
advance, even ceasing to use certain technologies and deliberately
reducing the economic wealth of the country.

Of course, as we know nothing about the biological, economic and
physical conditions on Throomia. There could be reasons we can't imagine
for the Throomians being unable or uninterested in PD.

There are at least two related issues to which you've given no adequate
treatment. These are, what would motivate any culture to undertake a DP
project, and why we should expect interest in, resolve to pursue, or
capacity to pursue a project of so long a term as DP to continue to
fruition.

Mitchell Coffey

[Mitchell Coffey]

[snip]

I don't know what you're referring to, and don't believe you've done any
such thing. Instead of being cute, and beating your own chest in
undefended triumph, why don't you just say what you mean?

Mitchell Coffey