Popper, "prohibited Observations, and Pagano-like Poppycock
Bill
overturn secular scientific orthodoxy and revitalize the Catholic
Church, bringing the wayward cafeteria Catholics back to the fold, and
reversing the terrible damage done to the human soul by the so-called
"Enlightenment." No doubt. No doubt whatsoever. In the face of his
unequalled genius and inevitable victory it is only with the greatest
of trepidation that I raise a few questions about his method of
deductive falsification, derived, he says, from Popper.
Tony argues that no amount of confirmatory evidence for a theory tells
you anything about its......(wait for it)....truthlikeness, but that a
single "prohibited observation" suffices to falsify the theory, with
all the certainty of rigorous deductive logic. I would prefer that he
spoke in terms of predictions, rather than prohibited observations,
but he has astutely noticed that clarity of language is not his friend
and thus shuns it. Here is his argument in brief.
Consider the chain of reasoning: (1) Theory A predicts observation X
(2) Observation X is observed (3) Therefore theory A is true. Pagano
correctly points out that this reasoning will not hold up, since any
number of other theories might also predict observation X. And simply
accumulating a whole lot of observations correctly predicted by Theory
A does nothing for you, since repeating a bad syllogism 10,000 times
doesn't make it a good syllogism.
On the other hand, consider the reasoning involved in falsification.
(1) Theory A predicts that X will not be observed (2) X is observed
(3) Theory A is false. That reasoning is absolutely airtight. So it
seems that while confirmation of a theory is inductive and therefore
unreliable and uninformative about the truthlikeness of a theory,
falsification is rigorously deductive and reliable.
Well, that's Tony's argument, anyway. With due regard to his undoubted
genius, it is the sort of argument that could only be made by someone
who'd never done any actual science. In mathematics and abstract logic
deductions are ironclad because one can simply make the premises true
by definition. In any question regarding the physical world it is
rather more difficult to have certain premises. For example, in any
specific experimental situation your calculation that observation X is
"prohibited" by the theory may be wrong. You may have overlooked
sources of background effects that you should have included in
figuring out what observations to expect (or not to expect). When you
observe X, the allegedly prohibited observation X might actually be
X', an observation compatible with Theory A. In trying to be certain
of your premises you are stuck using induction; so the conclusion of
falsification, which Tony thought was an ironclad, rigorous deduction,
rests on premises supported by poor old Humean induction. So
falsification is on no better a footing than confirmation.
In fact though, we rarely consider theories in isolation and attempt
to falsify them. We always consider competing theories and try to find
situations in which they make different predictions. Then we do the
experiment and see which theory's predictions are observed. This is
true even when it looks like we are simply trying to falsify a single
theory. Let's say we find the "prohibited observation" X. We then
consider several competing theories (1) Theory A is false (2) the
observation X was an error (3) our prediction that X should not be
observed if Theory A holds was wrong. Then we try to find experiments
we can do for which each of those possibilities makes a different
prediction of the result. And so on. [As a side point, without
induction one cannot conclude that observation X was anything but a
fluke with no bearing on the falsity of Theory A whatsoever - see,
Tony, you cannot get anywhere if you are unwilling to use induction].
Tony thrives on obscurely worded generalities, but it will be easier
to understand falsification if we use a specific example. So one case
in which it's pretty close to true that physicists falsified a theory
in the absence of a better alternative is the case of the classical
predictions for the spectrum of electromagnetic radiation from a black
body (that's a body that absorbs all EM radiation that shines on it,
regardless of frequency). The classical prediction, summarized IIRC in
Rayleigh's equation was that the intensity of radiation from a black
body at any given wavelength would increase monotonically for shorter
and shorter wavelengths. That was wrong. It would have predicted, for
example, that if you peeped into the right sort of hot furnace you'd
have been instantly killed by high energy gamma radiation. In fact,
there was a peak in the intensity vs frequency graph, not a monotonic
increase. Ultimately, this helped get quantum mechanics started, but
at first it just falsified classical electromagnetics. But even here,
the physicists considered alternatives of the sort I mentioned above.
Many of them went over and over the derivation of Rayleigh's equation
to make sure that it's prediction of a monotonic increase was in fact
what classical EM theory predicted. Others looked for errors in the
observations - a perfect black body is an idealized thing, and it
might have been that the experimental apparatuses differed from an
ideal black body in ways that could account for the prohibited
observation. It was only when there was a good alternate theory for
black body radiation, based on quantum mechanics, that it became
clear, in retrospect, that the classical EM theory had been falsified.
And quantum mechanics still had to be shown to be compatible with all
of the successful predictions made by classical EM theory in other
settings. That's where confirmatory evidence has weight. Classical EM
explained an awful lot of disparate observations in many different
settings - you could not easily dump it without an alternative that
explained all of those observations AND ALSO explained black body
radiation.
You could summarize it as (1) Classical EM predicts that there is no
peak in the plot of intensity versus frequency in black body radiation
(2) a clear peak in the plot was observed (3) Classical EM theory is
false.
You *could* summarize it that way, and Tony would like to do so, but
such a summary would have left out all the competing theories that
were actually in play while this was being worked on.
So now, let's put Tony's ID based falsification of the theory of
evolution in the same format. The argument would be (1) NeoDarwinism
predicts that the only biological structures that can exist are those
which can have evolved as a result of mutation and selection (2) there
is at least one structure, for example the biological flagellum, which
cannot possibly have evolved as a result of mutation and natural
selection (3) therefore NeoDarwinism is false.
It's hard to disagree with step (1). But step (2) is the crux of the
matter. If this falsification is to work deductively and be ironclad,
then we must know with all the certainty of a geometric definition
that the evolution of the bacterial flagellum is an impossibility. The
burden is on the falsifier to show where the impossible step in any
proposed pathway lies. It's actually a really rough road to try to
take towards falsifying the ToE. It would be far easier to try to show
that morphological and DNA sequencing based phylogenies were
contradictory, or that human and trilobite fossils were found in the
same strata. Those are potentially objective reproducible observations
that would falsify the ToE. Much stronger than "I just don't see how
it could have evolved."
So, in brief, contra Tony, confirmatory evidence does matter. The more
correct predictions a theory makes in a range of circumstances, the
truer the theory is. Falsifying evidence matters, too, of course, but
falsification depends on induction and on the consideration of
competing hypotheses just as surely as does confirmation. There's
nothing deductively airtight about falsification.
In the end it is impressive that in spite of all the philosophical
name dropping and the delightfully obscure philosophical posing,
Tony's argument just comes down to "I don't see how anything so
complicated could have evolved."
rmacfarl
"Bill" <broger...@gmail.com> wrote in message
news:5e6fb726-2878-495b...@42g2000prb.googlegroups.com...
T Pagano
<broger...@gmail.com> wrote:
>There is no doubt that Pagano is a revolutionary genius destined to
>overturn secular scientific orthodoxy and revitalize the Catholic
>Church, bringing the wayward cafeteria Catholics back to the fold, and
>reversing the terrible damage done to the human soul by the so-called
>"Enlightenment." No doubt. No doubt whatsoever. In the face of his
>unequalled genius and inevitable victory it is only with the greatest
>of trepidation that I raise a few questions about his method of
>deductive falsification, derived, he says, from Popper.
>
>Tony argues that no amount of confirmatory evidence for a theory tells
>you anything about its......(wait for it)....truthlikeness,
No amount of confirmatory evidence tells us that some universal theory
is true or even probably true. This is the Problem of Induction. As
far as I know Hume never discussed truthlikeness--that is, closeness
to the truth. The process called Induction is logicall invalid.
>but that a
>single "prohibited observation" suffices to falsify the theory, with
>all the certainty of rigorous deductive logic.
Falsification is certainly deductive. However even falsifications are
provisional for a variety of reasons. Nonetheless a single
observation prohibited by some theory is enough to bring it down.
> I would prefer that he
>spoke in terms of predictions, rather than prohibited observations,
>but he has astutely noticed that clarity of language is not his friend
>and thus shuns it. Here is his argument in brief.
Predictions and Prohibitions are both entailed by a genuinely
scientific theory; they are apples and oranges. Predictions tell us
what we should see and Prohibitions tell us what we shouldn't see.
>
>Consider the chain of reasoning: (1) Theory A predicts observation X
>(2) Observation X is observed (3) Therefore theory A is true. Pagano
>correctly points out that this reasoning will not hold up, since any
>number of other theories might also predict observation X. And simply
>accumulating a whole lot of observations correctly predicted by Theory
>A does nothing for you, since repeating a bad syllogism 10,000 times
>doesn't make it a good syllogism.
Never claimed that a universal theory with corroborative evidence is
of no value. Regularities may have been identified in a narrow domain
which may be exploited. However the corroborations do not tell us
whether the universal theory is true over its whole domain for which
observations have not been made or can not be made.
>
>On the other hand, consider the reasoning involved in falsification.
>(1) Theory A predicts that X will not be observed (2) X is observed
>(3) Theory A is false. That reasoning is absolutely airtight. So it
>seems that while confirmation of a theory is inductive and therefore
>unreliable and uninformative about the truthlikeness of a theory,
>falsification is rigorously deductive and reliable.
>Well, that's Tony's argument, anyway
Not quite.
Hume's problem of induction doesn't address reliability, truthlikeness
or information content. The Problem of Induction simply states that
the observations that we can make do NOT prove the truth of a
universal theory which explains events that have not been observed or
cannot be observed. The corroborative observations don't even prove
that the universal theory is probably true.
>
>. With due regard to his undoubted
>genius, it is the sort of argument that could only be made by someone
>who'd never done any actual science. In mathematics and abstract logic
>deductions are ironclad because one can simply make the premises true
>by definition.
Sadly Bill doesn't understand science very well. Who claimed that
falsifications were ironclad? I claimed only that they are deductive
and provisional. If the premises of some falsification argument are
false then so will the conclusion. That is, We may have incorrectly
attributed a prohibition to a theory. Or the observation of a
prohibited event may not be reproduced calling the falsification into
question.
However, if we are lucky enough to determine the prohibition and
accurately find it then we can be sure that the theory is false.
The rest snipped.
Regards,
T Pagano
Richard Clayton
> Nominated...
Seconded.
(Perhaps we should prepare for PotM pooh-poohing from Punch-Drunk Pagano.)
--
[The address listed is a spam trap. To reply, take off every zig.]
Richard Clayton
"I keep six honest serving men (they taught me all I knew); their names
are What and Why and When and How and Where and Who." � Rudyard Kipling
Bill
> On Fri, 28 May 2010 18:14:08 -0700 (PDT), Bill
>
Gee Tony, there may be progress here. You seem to be accepting that
(1) corroborative evidence for a theory tells you something (though of
course not that the theory is "universally true." (2) falsifications
are provisional [ you also may recognize that the accuracy of the
premises involved in the falsification depend on induction. What you
further seem to claim though is that while observation may suggest
"regularities in nature" they do not tell you about the "universal
truth" of your theories.
OK. The absolute, guaranteed truth of mathematical propositions
follows from definitions and axioms. If your definitions and axioms
are accepted (and they can simply be declared to be true within your
mathematical system) the conclusions you draw are true with a capital
T, as long as you make no mistakes in your reasoning. So you can get
to "universal truth" in mathematics.
The natural world is different, though. The only way you can make
theories about the natural world is on the basis of observations. You
generalize based on induction. I'm not a post modernist, so I think
that there is a Truth about the natural world, but I'm also a
scientist so I recognize that we do not have direct access to that
Truth. All we have are progressive approximations. A theory is good to
the extent that it makes correct predictions over a range of
conditions. You may say that this tells you nothing about the truth,
but it seems pretty clear that a theory that makes a lot of correct
predictions is telling you something true about the world. Hume did
not think this inductive process was not valid, only that it was not
based on logic. His conclusion was that useful truths could be reached
by methods other than logical deduction. Sure, the theories are only
approximations of the truth, but with care and hard work you can get
the approximation better and better. You think this is a lack of
interest in the truth. I think it's a recognition that truth is really
hard to come by.
You, of course, have an omniscient/omnipotent Being who provides you
guaranteed truths about the natural world. Those of us without such a
direct line to truth like that just have to work harder.
Bill
>
> The rest snipped.
>
> Regards,
> T Pagano
You do know, Tony, that Hume didn't actually use the phrase "Problem
of Induction," don't you? You *really* should read Hume. It would make
it so much easier to understand his ideas. Start with "An Enquiry
Concerning Human Understanding." Then, if you can stomach the "rabid
atheism" of it all, try "On the Natural History of Religion." You
might like his "Dialogue on Natural Religion," except that to judge by
the way you tend to misread posts here, I suspect you'd be confused
about which point of view Hume supported in the dialogues. The
Treatise on Morals is also enjoyable, and still, I think pretty
correct.
My work is done here. More later, if time permits. This is too easy,
drill sergeant. Set 'em up and knock 'em down. Time for the Mercy
Rule? Rest snipped as a waste of time. I'm gonna squidge my toes in
the wet sand on the beach and watch those waves of "calm, global-like
flooding" lapping at my feet. How therapeutic; I'll have recovered
from this last drubbing in no time at all.