Moral Realism and Dishonesty (was: Knowing we couldn't know)
George Dance
cd...@posting.google.com>...
> George Dance <georg...@hotmail.com> wrote in message news:<6312c50b.0206
> 080656....@posting.google.com>...
>
> > His only argument for that, if you remember, has been his 'knowledge
> > possibility principle': It is possible to know that W is false, and
> > impossible to know that W is true.
>
>
> That isn't even close to my 'principle.' I think now is an appropriate
> time to bring back the charges of dishonesty.
If so, it's also time to back them up.
Your claim is:
<quote>
> (1) We can know that moral realism is false, and (2) If
> it weren't false, we couldn't know either way.
<quote>
Which logically implies that (3) it is possible to know that moral
realism is false, and (4) it is impossible to know that moral realism
is true.
If you know that (1) moral realism is false, then: it (3) is possible
to know that moral realism is false. (1) strictly implies (3).
If you know that (2) if moral realism were true, you couldn't know
either way, then: if moral realism were true, you couldn't know that
moral realism was true. As well, if moral realism were false, you
couldn't know that moral realism was true. Moral realism is either
true or false; and either way, you couldn't know that moral realism
was true. So you cannot know that moral realism was true, at any
time, or IOW (4) it is impossible to know that moral realism is true.
(2) strictly implies (4).
If your 'principle' claims both (1) and (2), and if (1) strictly
implies (3) and (2) strictly implies (4), then your 'principle'
strictly implies (3) and (4). QED
Symmetry
> Symmetry <symm...@aol.com> wrote in message news:<30b3ec10.0206091141.767b
> cd...@posting.google.com>...
>
> > George Dance <georg...@hotmail.com> wrote in message news:<6312c50b.0206
> > 080656....@posting.google.com>...
> >
> > > His only argument for that, if you remember, has been his 'knowledge
> > > possibility principle': It is possible to know that W is false, and
> > > impossible to know that W is true.
> >
> >
> > That isn't even close to my 'principle.' I think now is an appropriate
> > time to bring back the charges of dishonesty.
>
> If so, it's also time to back them up.
>
> Your claim is:
>
> <quote>
> > (1) We can know that moral realism is false, and (2) If
> > it weren't false, we couldn't know either way.
> <quote>
>
> Which logically implies that (3) it is possible to know that moral
> realism is false, and (4) it is impossible to know that moral realism
> is true.
[snip simple derivation]
> If your 'principle' claims both (1) and (2), and if (1) strictly
> implies (3) and (2) strictly implies (4), then your 'principle'
> strictly implies (3) and (4). QED
Your claim was that my principle *was* X (X is what you call my
principle in your first quoted text).
What you show above is that you can derive my principle from X. To
show that X is actually equivilant to my principle, you also need to
show that X implies my principle. You haven't done this.
If you look closely at X, you'll see its the same thing I keep
pointing out to you as trivially true. I keep warning you that you
make an error every time you translate "we can know A, and if A were
false, then we couldnt know A" to "we can know A, and we cannot know
~A"
Those are different claims, yet you must have made the same elementary
mistake in confusing them at least 5 times by now.
To refresh your memory, I've never held that what said was my
principle above was false. I pointed out that its trivially true that
if we can know A, then since we can't know a falsity, we can't know
that ~A.
My correct statement was that that wasn't my principle, and your
attempt to show otherwise by only proving that my principle implied
what you said was my principle was logically faulty.
By the way, the illustrious Mark Young has shown you some errors in
your argument against me. I note that you haven't responded to him
though. Why is that?
Symmetry
> Symmetry <symm...@aol.com> wrote in message news:<30b3ec10.0206091141.767b
> cd...@posting.google.com>...
>
> > George Dance <georg...@hotmail.com> wrote in message news:<6312c50b.0206
> > 080656....@posting.google.com>...
> >
> > > His only argument for that, if you remember, has been his 'knowledge
> > > possibility principle': It is possible to know that W is false, and
> > > impossible to know that W is true.
> >
> >
> > That isn't even close to my 'principle.' I think now is an appropriate
> > time to bring back the charges of dishonesty.
>
> If so, it's also time to back them up.
>
> Your claim is:
>
> <quote>
> > (1) We can know that moral realism is false, and (2) If
> > it weren't false, we couldn't know either way.
> <quote>
>
> Which logically implies that (3) it is possible to know that moral
> realism is false, and (4) it is impossible to know that moral realism
> is true.
[snip simple derivation]
> If your 'principle' claims both (1) and (2), and if (1) strictly
> implies (3) and (2) strictly implies (4), then your 'principle'
> strictly implies (3) and (4). QED
Your claim was that my principle *was* X (X is what you call my
Eudaimonus
> To refresh your memory, I've never held that what said was my
> principle above was false. I pointed out that its trivially true that
> if we can know A, then since we can't know a falsity, we can't know
> that ~A.
Beware modal notions - they can really mess you up when you start forgetting
just precisely their range of scope. For instance, your arguement is as
follows :
possible(know(A))
therefor
~possible(know(A)&~A)
therefor
~possible(know(~A))
Obviously, there is much of the logic you used, left implied - let me try to
bring it out
1 : possible(know(A))
T1 : know(A)->A [theorum]
2 : possible(A) [from 1 & T1]
3 : ~possible(~A) [from 2]
T2 : know(~A)-> ~A [same theorum in different form]
4 : ~possible(know(~A)) [from 3 & T2]
The problem here, is that possible(A)->~possible(~A) is not a valid
infernece.
As it is possible, for both A and ~A to be possible, then it is possible for
it to be both possible to know A, and possible to know ~A.
You can say that, either it is possible to know A, only if A, and it is
possible to know ~A, only if ~A, but the point is that just because A is
possible, does not make ~A impossible (it is only A's being _actual_ that
makes ~A's being _actual_, and thus being 'possibly' known, impossible).
In short, "we can know A" does not imply A - it only implies "A could be",
which is something quite different.
George Dance
7c...@posting.google.com>...
(Second attempt to reply)
> George Dance <georg...@hotmail.com> wrote in message news:<6312c50b.0206
> 290954....@posting.google.com>...
> > Symmetry <symm...@aol.com> wrote in message news:<30b3ec10.0206091141.767b
> > cd...@posting.google.com>...
> >
> > > George Dance <georg...@hotmail.com> wrote in message news:<6312c50
> > > b.0206
> > > 080656....@posting.google.com>...
> > >
> > > > His only argument for that, if you remember, has been his 'knowledge
> > > > possibility principle': > > >
> > >
> > > That isn't even close to my 'principle.' I think now is an appropriate
> > > time to bring back the charges of dishonesty.
> >
> > If so, it's also time to back them up.
> >
> > Your claim is:
> >
> >
> > Which logically implies that (3) it is possible to know that moral
> > realism is false, and (4) it is impossible to know that moral realism
> > is true.
>
> [snip simple derivation]
>
> > If your 'principle' claims both (1) and (2), and if (1) strictly
> > implies (3) and (2) strictly implies (4), then your 'principle'
> > strictly implies (3) and (4). QED
>
> Your claim was that my principle *was* X (X is what you call my
> principle in your first quoted text).
Let me see if I understand you. By your 'principle' I think you mean:
Symmetry's 'principle':
> > <quote>
> > > (1) We can know that moral realism is false, and (2) If
> > > it weren't false, we couldn't know either way.
> > <quote>
And by X I think you mean:
X:
It is possible to know that W is false, and
> > > > impossible to know that W is true.
> What you show above is that you can derive my principle from X.
I don't think so. I showed that your principle entails X, so X can be
derived from your principle.
> To
> show that X is actually equivilant to my principle, you also need to
> show that X implies my principle. You haven't done this.
To derive your principle from X, you need a further premise, to the
effect that "we can know one way or another." I'm not challenging
your use of that.
> If you look closely at X, you'll see its the same thing I keep
> pointing out to you as trivially true.
X is certainly not 'trivially true.'
> I keep warning you that you
> make an error every time you translate "we can know A, and if A were
> false, then we couldnt know A" to "we can know A, and we cannot know
> ~A"
You got half of your 'principle' wrong; in fact, your claim there is
that "if A were false (ie, if ~A were true), then we couldn't know A
or ~A"; and that does 'translate' (as the proof that you snipped
showed) to "we cannot know ~A." And the other half, "we can know A,"
does 'translate' to "we can know A."
> Those are different claims, yet you must have made the same elementary
> mistake in confusing them at least 5 times by now.
It's a simple deduction (or 'simple derivation') as you put it from
one to the other.
> To refresh your memory, I've never held that what said was my
> principle above was false.
???
I pointed out that its trivially true that
> if we can know A, then since we can't know a falsity, we can't know
> that ~A.
It does not follow, from "we can know A," that "A is true". All that
follows from "we can know A" is that "A can be true;" and it does not
follow, from "A can be true," that ~A is a 'falsity.' It is true that
if ~A is false, then we cannot know ~A; however, you haven't shown
that ~A is a 'falsity.' That's beside the point anyway, since your
'principle' states that if ~A is true, then we cannot know ~A.
> My correct statement was that that wasn't my principle, and your
> attempt to show otherwise by only proving that my principle implied
> what you said was my principle was logically faulty.
You neither claimed a 'logical fault' (the word you used was
'dishonesty') nor have showed one in my proof; you have showed quite a
few above, though I don't think intentionally.
snip - oot
George Dance
7c...@posting.google.com>...
> By the way, the illustrious Mark Young has shown you some errors in
> your argument against me. I note that you haven't responded to him
> though. Why is that?
Actually, I did write a reply to the illustrious Mr. Young; but it
didn't show up on the board, and I didn't bother with a rewrite, for a
few reasons:
First, I found the 'errors' that the illustrious Mr. Young pointed out
were grammatical rather than logical - that I used the word 'that'
rather than 'whether' in one case, and 'was true' rather than the
subjunctive 'were true' in another. The first, as the illustrious Mr.
Young pointed out, did not affect my argument; whether the second did,
depends on whether it is carried over into a symbolic proof.
Scond, while the illustrious Mr. Young did provide a formalization, it
was not one that I found particularly useful; and since you also
objected to it, I saw lttle point in turning it into something from
which a proof could be generated.
Third, it was not clear how the illustrious Mr. Young himself used his
formalization to derive a conclusion - as his argument consisted of
first giving the formalization, and immediately afterward declaring
that the conclusion was 'clear' to him. I cannot see much value in
discussing the logical form of *that* kind of argument, even with the
illustrious Mr. Young.
George Dance
.27111@sccrnsc01>...
> "Symmetry" <symm...@aol.com> wrote in message
> news:30b3ec10.02070...@posting.google.com...
> > To refresh your memory, I've never held that what said was my
> > principle above was false.
???
Very well put. I think that's the easiest mistake to make in modal
logic (certainly it's one that I made once upon a time, without trying
too hard 8).
Where Symmetry's error comes from, I think, is the natural language
form of sentences like "If my computer is on, it's impossible for it
to not be on." Strictly speaking, if I said that, it would be false -
my computer is on because it's plugged in and switched on, and that
both those facts are contingent are reasons it's possible for my
computer to not be on.
If I heard someone say that, though, I would intepret the statement as
the same proposition (ie, equivalent to the same statement) as, "It is
impossible that, if my computer is on, it is not on." - which *is*
trivially true.
The second statement has the modal form ~<>(T->~T); the first,
T->~<>~T. Confusing those two is known as Sleigh's Fallacy or
Misconditionalization.
Symmetry
> news:30b3ec10.02070...@posting.google.com...
>
> > To refresh your memory, I've never held that what said was my
> > principle above was false. I pointed out that its trivially true that
> > if we can know A, then since we can't know a falsity, we can't know
> > that ~A.
>
> Beware modal notions - they can really mess you up when you start forgetting
> just precisely their range of scope. For instance, your arguement is as
> follows :
>
> possible(know(A))
> therefor
> ~possible(know(A)&~A)
This second statement doesn't really rely on the first for
justification.
> therefor
> ~possible(know(~A))
>
> Obviously, there is much of the logic you used, left implied - let me try to
> bring it out
>
> 1 : possible(know(A))
> T1 : know(A)->A [theorum]
> 2 : possible(A) [from 1 & T1]
Well, in my examplpe A was definitely true, so asying its only
possible is true but an understatement.
> 3 : ~possible(~A) [from 2]
No, this doesn't follow from 2. However, this is true by stipulation.
In my scenario A is true.
> T2 : know(~A)-> ~A [same theorum in different form]
Actually the form is the same.
> 4 : ~possible(know(~A)) [from 3 & T2]
>
> The problem here, is that possible(A)->~possible(~A) is not a valid
> infernece.
Of course not, and I never make such an inference. You seem to be
misinterpreting what I have said.
> As it is possible, for both A and ~A to be possible, then it is possible for
> it to be both possible to know A, and possible to know ~A.
Again, in my scenario A is true.
It seems you've gotten confused by translating my "can" into some
fancy formal notion of possibly, and then applying it to the truth of
A when I never said anything about how A 'can be true' or not.
> You can say that, either it is possible to know A, only if A, and it is
> possible to know ~A, only if ~A, but the point is that just because A is
> possible, does not make ~A impossible
Indeed. I never said otherwise.
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Symmetry
> news:30b3ec10.02070...@posting.google.com...
>
> > To refresh your memory, I've never held that what said was my
> > principle above was false. I pointed out that its trivially true that
> > if we can know A, then since we can't know a falsity, we can't know
> > that ~A.
>
> Beware modal notions - they can really mess you up when you start forgetting
> just precisely their range of scope. For instance, your arguement is as
> follows :
>
> possible(know(A))
> therefor
> ~possible(know(A)&~A)
This second statement doesn't really rely on the first for
justification.
> therefor
> ~possible(know(~A))
>
> Obviously, there is much of the logic you used, left implied - let me try to
> bring it out
>
> 1 : possible(know(A))
> T1 : know(A)->A [theorum]
> 2 : possible(A) [from 1 & T1]
Well, in my examplpe A was definitely true, so asying its only
possible is true but an understatement.
> 3 : ~possible(~A) [from 2]
No, this doesn't follow from 2. However, this is true by stipulation.
In my scenario A is true.
> T2 : know(~A)-> ~A [same theorum in different form]
Actually the form is the same.
> 4 : ~possible(know(~A)) [from 3 & T2]
>
> The problem here, is that possible(A)->~possible(~A) is not a valid
> infernece.
Of course not, and I never make such an inference. You seem to be
misinterpreting what I have said.
> As it is possible, for both A and ~A to be possible, then it is possible for
> it to be both possible to know A, and possible to know ~A.
Again, in my scenario A is true.
It seems you've gotten confused by translating my "can" into some
fancy formal notion of possibly, and then applying it to the truth of
A when I never said anything about how A 'can be true' or not.
> You can say that, either it is possible to know A, only if A, and it is
> possible to know ~A, only if ~A, but the point is that just because A is
> possible, does not make ~A impossible
Indeed. I never said otherwise.
Symmetry
032139....@posting.google.com>...
Well, that is my claim. What you have been calling my 'principle' is a
more generalized claim which doesnt specifically deal w/ moral
realism.
> And by X I think you mean:
>
> X:
> It is possible to know that W is false, and
> > > > > impossible to know that W is true.
Yes, but looking at that now though, W is unspeciied so the claim
doesn't make sense. I originally interpreted it with "there exists
some W such that ..." preceding it. That is what I said was trivially
true.
Here is why: There is at least one thing that is false such that we
can know it is false. Consider one such thing, call it W. Since we
can't know a falsity, we cannot know that W.
> > What you show above is that you can derive my principle from X.
>
> I don't think so. I showed that your principle entails X, so X can be
> derived from your principle.
Indeed, I phrased that backwards., as can be seen by my later comments
in which I talk about showing X implies my principle.
> > To
> > show that X is actually equivilant to my principle, you also need to
> > show that X implies my principle. You haven't done this.
>
> To derive your principle from X, you need a further premise, to the
> effect that "we can know one way or another." I'm not challenging
> your use of that.
>
> > If you look closely at X, you'll see its the same thing I keep
> > pointing out to you as trivially true.
>
> X is certainly not 'trivially true.'
Sure it is. See above. If there is anything which we can know is false
(which there is), then since we can't know a falsity, etc etc etc.. It
is qite trivial indeed.
>
> > I keep warning you that you
> > make an error every time you translate "we can know A, and if A were
> > false, then we couldnt know A" to "we can know A, and we cannot know
> > ~A"
>
> You got half of your 'principle' wrong; in fact, your claim there is
> that "if A were false (ie, if ~A were true), then we couldn't know A
> or ~A";
Yes, I phrased my principe incorrectly the first time. It should be as
you point out now.
> and that does 'translate' (as the proof that you snipped
> showed) to "we cannot know ~A."
No, it doesn't. It implies that we cannot know ~A, but they are not
equivilant. That we cannot know ~A doesn't imply that if ~A were true,
then we couldn't know it. Try to immagine cases where A is true to see
why.
In short, your (3) and my (1) are equivilant as far as I remember, but
your (4) and my (2) are edfinitely not equivilant, and thus your
version of my principle is not equivilant to my principle.
> And the other half, "we can know A,"
> does 'translate' to "we can know A."
Yes, very good.
> > Those are different claims, yet you must have made the same elementary
> > mistake in confusing them at least 5 times by now.
>
> It's a simple deduction (or 'simple derivation') as you put it from
> one to the other.
But not back from the other to the one, unfortunately.
>
> It does not follow, from "we can know A," that "A is true". All that
> follows from "we can know A" is that "A can be true;"
You're probably misinterpreting me. When I say 'we can know A', the
'world' I am referring to is fixed. In fact it is our current world.
The only world in which that statement is true is one in which A is
true. In such a fixed world where A is true, no one can ever know ~A.
> It is true that
> if ~A is false, then we cannot know ~A; however, you haven't shown
> that ~A is a 'falsity.'
If we can know A in our current, fixed world, then it is impossible
for ~A to be true in our world. When I say that we can know A I'm not
just saying our world might be one in which A is true (and some other
stuff).
> That's beside the point anyway, since your
> 'principle' states that if ~A is true, then we cannot know ~A.
No, it states that if ~A WERE true, then we COULDN"T know ~A.
They're very different.
Look:
If A is true, then any conditional beginning with "if ~A IS true" is
true. Your mistranslated version of my principle runs into this issue.
I don't know how many times you can make this error.
>
> > My correct statement was that that wasn't my principle, and your
> > attempt to show otherwise by only proving that my principle implied
> > what you said was my principle was logically faulty.
>
> You neither claimed a 'logical fault' (the word you used was
> 'dishonesty') nor have showed one in my proof; you have showed quite a
> few above, though I don't think intentionally.
The logical fault was in thinking that 'one way' implication proved
equivilance. It appears that you actually thought your 2 and my 4 were
equivilant though, which just means you made a different kind of
error.
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George Dance
3...@posting.google.com>...
> George Dance <georg...@hotmail.com> wrote in message news:<6312c50b.0207
> 032139....@posting.google.com>...
> > Let me see if I understand you. By your 'principle' I think you mean:
> >
> > Symmetry's 'principle':
> > > > <quote>
> > > > > (1) We can know that moral realism is false, and (2) If
> > > > > it weren't false, we couldn't know either way.
> > > > <quote>
>
> Well, that is my claim. What you have been calling my 'principle' is a
> more generalized claim which doesnt specifically deal w/ moral
> realism.
That is the only real-world example you've given of it; though
admittedly there may be others.
> > And by X I think you mean:
> >
> > X:
> > It is possible to know that W is false, and
> > > > > > impossible to know that W is true.
>
> Yes, but looking at that now though, W is unspeciied so the claim
> doesn't make sense.
No, W was explicitly defined up above. I'm not going back to look for
it now, as that would mean rewriting; but you can look it up for
yourself - I believe it was the statement, "It's wrong to kill kittens
in a blender for fun."
> I originally interpreted it with "there exists
> some W such that ..." preceding it. That is what I said was trivially
> true.
Indeed you did.
> Here is why: There is at least one thing that is false such that we
> can know it is false. Consider one such thing, call it W. Since we
> can't know a falsity, we cannot know that W.
All right; let W be "my radio is on" - that's false, and I know it's
false.
Excuse me for a minute.
Now W is true, and I know it's true - which you claim is impossible.
> > > To
> > > show that X is actually equivilant to my principle, you also need to
> > > show that X implies my principle. You haven't done this.
> >
> > To derive your principle from X, you need a further premise, to the
> > effect that "we can know one way or another." I'm not challenging
> > your use of that.
So there was no claim of equivalence; just one of implication.
> > > If you look closely at X, you'll see its the same thing I keep
> > > pointing out to you as trivially true.
> >
> > X is certainly not 'trivially true.'
>
> Sure it is. See above. If there is anything which we can know is false
> (which there is), then since we can't know a falsity, etc etc etc.. It
> is qite trivial indeed.
Then why do I know my radio is on, if it was possible for me to know
it was off?
> >
> > You got half of your 'principle' wrong; in fact, your claim there is
> > that "if A were false (ie, if ~A were true), then we couldn't know A
> > or ~A";
>
> Yes, I phrased my principe incorrectly the first time. It should be as
> you point out now.
>
> > and that does 'translate' (as the proof that you snipped
> > showed) to "we cannot know ~A."
>
> No, it doesn't. It implies that we cannot know ~A,
which is what I claimed.
> but they are not
> equivilant.
which I did not claim.
That we cannot know ~A doesn't imply that if ~A were true,
> then we couldn't know it.
That's wrong. Suppose it were true that we couldn't know ~A, period;
then, if B were true (no matter what B is), then we couldn't know ~A.
> Try to immagine cases where A is true to see
> why.
OK; it's true that my radio is on, which (you claim) makes it
'trivially true' that I cannot know that my radio was off. Therefore,
by your claim, if my radio were off, I couldn't know that it was off.
> In short, your (3) and my (1) are equivilant as far as I remember, but
> your (4) and my (2) are edfinitely not equivilant, and thus your
> version of my principle is not equivilant to my principle.
>
> > And the other half, "we can know A,"
> > does 'translate' to "we can know A."
>
> Yes, very good.
>
> > > Those are different claims, yet you must have made the same elementary
> > > mistake in confusing them at least 5 times by now.
> >
> > It's a simple deduction (or 'simple derivation') as you put it from
> > one to the other.
>
> But not back from the other to the one, unfortunately.
Remember, I didn't claim equivalence; but it turns out you're wrong
about that, too:
1. It's impossible to know X.
--------------
2. Therefore, if X is true, it's impossible to know X.
- is a valid inference.
> > It does not follow, from "we can know A," that "A is true". All that
> > follows from "we can know A" is that "A can be true;"
>
> You're probably misinterpreting me. When I say 'we can know A', the
> 'world' I am referring to is fixed. In fact it is our current world.
> The only world in which that statement is true is one in which A is
> true. In such a fixed world where A is true, no one can ever know ~A.
OK; in our current world, my radio is on - and therefore, you're
claiming, no one can ever know my radio is on.
Excuse me for a minute.
Now my radio is off, and I know it's off - another contradiction!
> > It is true that
> > if ~A is false, then we cannot know ~A;
That phrasing was awkward - if we had actually progressed to formal
arguments, I would of course have written that as ~<>(~A&k(A)).
> > however, you haven't shown
> > that ~A is a 'falsity.'
>
> If we can know A in our current, fixed world, then it is impossible
> for ~A to be true in our world.
But I can know that my radio is on, in my current, fixed world.
Therefore, is it impossible for me to know that my radio is off?
Excuse me for a minute.
Nope, this is not working out.
> When I say that we can know A I'm not
> just saying our world might be one in which A is true (and some other
> stuff).
That last is what it means for A (whether A is "my radio is on" or
"there are no moral truths" or whatever) to be a contingent fact. So
what kind of a fact are you claiming that "there are no moral truths"
is, exactly?
> > That's beside the point anyway, since your
> > 'principle' states that if ~A is true, then we cannot know ~A.
>
> No, it states that if ~A WERE true, then we COULDN"T know ~A.
>
> They're very different.
Let's hear what you think is the difference.
> Look:
>
> If A is true, then any conditional beginning with "if ~A IS true" is
> true.
Which says exactly the same thing as "If A were true, then any
conditional beginning with "if ~A WERE true" would be true." IOW, no
difference whatsoever.
Your mistranslated version of my principle runs into this issue.
What exactly do you think is this 'issue' between 'If A is true..."
and "If A were true..."?
> I don't know how many times you can make this error.
I'll agree with the first three words of that.
> > You neither claimed a 'logical fault' (the word you used was
> > 'dishonesty') nor have showed one in my proof; you have showed quite a
> > few above, though I don't think intentionally.
>
> The logical fault was in thinking that 'one way' implication proved
> equivilance.
Actually, (a) I did not claim an equivalence, and (b) as I showed
above, the statements are equivalent in any case: "If ~A is true, we
cannot know ~A" implies "We cannot know ~A", and /vice versa/.
> It appears that you actually thought your 2 and my 4 were
> equivilant though, which just means you made a different kind of
> error.
Ho, hum...
Symmetry
> Symmetry <symm...@aol.com> wrote in message news:<30b3ec10.0207111050.106f
> 3...@posting.google.com>...
> > George Dance <georg...@hotmail.com> wrote in message news:<6312c50b.0207
> > 032139....@posting.google.com>...
>
> > > Let me see if I understand you. By your 'principle' I think you mean:
> > >
> > > Symmetry's 'principle':
> > > > > <quote>
> > > > > > (1) We can know that moral realism is false, and (2) If
> > > > > > it weren't false, we couldn't know either way.
> > > > > <quote>
> >
> > Well, that is my claim. What you have been calling my 'principle' is a
> > more generalized claim which doesnt specifically deal w/ moral
> > realism.
>
> That is the only real-world example you've given of it; though
> admittedly there may be others.
False, there was the kitten in the blender. Other people also gave
examples. Jones in the box, and then the guy who programmed his
computer, which related to coin flipping ( as far as I know you still
haven't responded to the situation in which he programs his computer
to forcibly restrain him or whatever ).
> > Here is why: There is at least one thing that is false such that we
> > can know it is false. Consider one such thing, call it W. Since we
> > can't know a falsity, we cannot know that W.
>
> All right; let W be "my radio is on" - that's false, and I know it's
> false.
>
> Excuse me for a minute.
>
> Now W is true, and I know it's true - which you claim is impossible.
No, I don't. You seem to be confusing your first "my radio is on"
claim with the second "my radio is on" claim. Those are not the same
proposition. They are made in different temporal contexts. To make
them explicit, you would write the first one as "at time <time t> my
radio is on" and the second as "at time <time r> my radio is on" with
r > t.
> > > > To
> > > > show that X is actually equivilant to my principle, you also need to
> > > > show that X implies my principle. You haven't done this.
> > >
> > > To derive your principle from X, you need a further premise, to the
> > > effect that "we can know one way or another." I'm not challenging
> > > your use of that.
>
> So there was no claim of equivalence; just one of implication.
Untrue. This is what you said:
"His only argument for that, if you remember, has been his 'knowledge
possibility principle': It is possible to know that W is false, and
impossible to know that W is true."
Obviously you claim that the above -is- my principle, and is not
merely implied by it.
> > > > If you look closely at X, you'll see its the same thing I keep
> > > > pointing out to you as trivially true.
> > >
> > > X is certainly not 'trivially true.'
> >
> > Sure it is. See above. If there is anything which we can know is false
> > (which there is), then since we can't know a falsity, etc etc etc.. It
> > is qite trivial indeed.
>
> Then why do I know my radio is on, if it was possible for me to know
> it was off?
See above for how you are confused in thinking that those two seperate
propositions are really the same one.
>
> > but they are not
> > equivilant.
>
> which I did not claim.
How do you explain this then:
"His only argument for that, if you remember, has been his 'knowledge
possibility principle': It is possible to know that W is false, and
impossible to know that W is true."
> That we cannot know ~A doesn't imply that if ~A were true,
> > then we couldn't know it.
>
> That's wrong. Suppose it were true that we couldn't know ~A, period;
> then, if B were true (no matter what B is), then we couldn't know ~A.
Again you seem confused by the difference between "if Q is true" and
"if Q were true." Btw, your claim seems to have no more content than
"if we couldn't know ~A, then we couldn't know ~A", or R-->R.. a
tautology.
> > Try to immagine cases where A is true to see
> > why.
>
> OK; it's true that my radio is on, which (you claim) makes it
> 'trivially true' that I cannot know that my radio was off. Therefore,
> by your claim, if my radio were off, I couldn't know that it was off.
Your text following 'therefore' is bad reasoning. Unfortunately your
free trial subscription to my logical tutoring has expired and I must
devote my time to more worthwhile things.
> > > > Those are different claims, yet you must have made the same elementary
> > > > mistake in confusing them at least 5 times by now.
> > >
> > > It's a simple deduction (or 'simple derivation') as you put it from
> > > one to the other.
> >
> > But not back from the other to the one, unfortunately.
>
> Remember, I didn't claim equivalence; but it turns out you're wrong
> about that, too:
>
> 1. It's impossible to know X.
> --------------
> 2. Therefore, if X is true, it's impossible to know X.
>
> - is a valid inference.
How many times can a person make the same error? This is rather
comical.
"if X were true" =/= "if X is true"
> > You're probably misinterpreting me. When I say 'we can know A', the
> > 'world' I am referring to is fixed. In fact it is our current world.
> > The only world in which that statement is true is one in which A is
> > true. In such a fixed world where A is true, no one can ever know ~A.
>
> OK; in our current world, my radio is on - and therefore, you're
> claiming, no one can ever know my radio is on.
>
> Excuse me for a minute.
>
> Now my radio is off, and I know it's off - another contradiction!
More comedy..
> > > That's beside the point anyway, since your
> > > 'principle' states that if ~A is true, then we cannot know ~A.
> >
> > No, it states that if ~A WERE true, then we COULDN"T know ~A.
> >
> > They're very different.
>
> Let's hear what you think is the difference.
You really aren't kidding? Read back over my last formal statement of
my principle, and also read Mark's formulation of my principle. I find
it very hard to believe that someone could understand the meaning of
Mark and I and then not know the difference between the two things
above.
>
> > > You neither claimed a 'logical fault' (the word you used was
> > > 'dishonesty') nor have showed one in my proof; you have showed quite a
> > > few above, though I don't think intentionally.
> >
> > The logical fault was in thinking that 'one way' implication proved
> > equivilance.
>
> Actually, (a) I did not claim an equivalence,
(a) has been shown to be wrong.
>and (b) as I showed
> above, the statements are equivalent in any case: "If ~A is true, we
> cannot know ~A" implies "We cannot know ~A", and /vice versa/.
No, you didn't, but I'm not going to be spending much more time on
you. You'll have to figure this one out youself. Maybe Mark Young will
help you if you ask him.
Symmetry
040716....@posting.google.com>...
> Symmetry <symm...@aol.com> wrote in message news:<30b3ec10.0207021023.494e
> 7c...@posting.google.com>...
>
> > By the way, the illustrious Mark Young has shown you some errors in
> > your argument against me. I note that you haven't responded to him
> > though. Why is that?
>
> Actually, I did write a reply to the illustrious Mr. Young; but it
> didn't show up on the board, and I didn't bother with a rewrite, for a
> few reasons:
>
> First, I found the 'errors' that the illustrious Mr. Young pointed out
> were grammatical rather than logical - that I used the word 'that'
> rather than 'whether' in one case, and 'was true' rather than the
> subjunctive 'were true' in another.
The latter two things generally do have a different meaning. I'd need
to see context to tell if the first two also have a different meaning.
Anyway now that I am no longer going to be trying to help you, it
would probably serve you well to reply to Mark Young and see if he can
teach you anything. He will be less apt to make fun of you which may
mesh better with your 'learning style' than my methods did.
> Scond, while the illustrious Mr. Young did provide a formalization, it
> was not one that I found particularly useful; and since you also
> objected to it, I saw lttle point in turning it into something from
> which a proof could be generated.
My objection to it was very minor and it turned out that I didn't need
to object after all (which you'd discover if you read our ensuing
dialogue and saw that I had assumed he meant all possible worlds when
he really hadnt). From what I remember of it, I support Mark's
formalization.
> Third, it was not clear how the illustrious Mr. Young himself used his
> formalization to derive a conclusion - as his argument consisted of
> first giving the formalization, and immediately afterward declaring
> that the conclusion was 'clear' to him. I cannot see much value in
> discussing the logical form of *that* kind of argument
What you are referring to is Mark overestimating of you. If you kindly
explain to him that you don't see how it is clear, then if he has
time, he will probably be nice enough to help you.