tronvillain

excreationist:
I do not know about Hawkingfan, but I have heard about Karl Popper. I am unimpressed.

anonymousj

quote:
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[Could you]show me how the existence of a perpetual motion machine is possible?
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To which Clutch responded,

So, can I show that it is possible that (P & ~P) is true by simply saying "Sure. It may be possible in the event that one or more of your beliefs..." about the laws of logic is mistaken.

aj

Clutch

Anonymousj,Sure. But not interestingly less.Well, a read of the actual words of my actual posts would suggest that I'm talking about empirical beliefs. But to accomodate your interest, let me say that, in my view, there is a serious question about whether something can be known in advance to be a non-empirical belief; eg, the geometry of space was not thought empirically assailable in some quarters.

As for your specific example: the defenders of paraconsistent or dialethic logics do regard it as a discovery -- albeit not a particularly empirical one -- that there can be true instances of (P&~P). (I presume that's what your dubious phrase "(P & ~P) is true" was meant to express.) So if one of your beliefs about the "laws of logic" was that LNC is an unrestricted axiom of every system of logic, then yes, the dialethicist will offer reasons why you should regard that belief as mistaken.

excreationist

Then the certainty that you are correct is 99.99999999999999.....% rather than 100.000000000000...%. Being 100% certain means exactly 100%, not slightly less than 100%.

excreationist

My point was just that science isn't 100.0000000......% certain.

That article talked about things being even more uncertain than Popper said:
"...Falsification may be based on faulty observation. A man who claims he saw a white crow could be mistaken or even lying...."

So people can't really be certain that the hypothesis that "all crows are black" was falsified after all...

anonymousj

Clutch,

As I understood your post to Hawkingfan, you offered an attempt to show that it is less than certain that a perpetual motion machines is impossible. Is this a misinterpretation? Were you merely attempting to describe something that might be called 'the logic of showing to be possible' or 'the logic of showing to be less than certain'? I thought I understood the import of your remarks until you responded to my post. Pehaps you can clarify this a bit.

Will you agree that one cannot show that it is possible that a belief that LNC is an unrestricted axiom of every system of logic might not be true by merely saying that 'the dialethicist will offer reasons why you should regard that belief as mistaken'. Will you agree that one cannot show that it is possible that a belief that LNC is an unrestricted axiom of logic might not be true by producing a dialethicist who offers reasons (he/she thinks show) why one should regard that belief as mistaken?

There is more to say, but not now...

aj

tronvillain

excreationist:
Oh, I am not about to argue with you about that, I am just not a fan of Popper.

Clutch

anonymousj, I've explained my point clearly and more than once. There is a difference between what it's reasonable or consistent to believe, given a set of antecedent commitments, and whether it is reasonable or consistent to entertain the prospect of states of information on which those commitments are themselves overturned, restricted, modified, attenuated, or what have you.

I have not in general dealt with the question of truth, but with what it's reasonable to believe. There is meta-inductive evidence, for both empirical and non-(or less?)-empirical domains, to show that one never knows with certainty what data or conceptual revolutions may come yet. Hence it is never warranted to pronounce the implicata of our current best ways of thinking to be absolutely certain. They may be certain relative to those ways of thinking, but those ways of thinking themselves are hostage to the prospect of unforeseen intellectual developments.

By the way: it is simply not true that LNC is an unrestricted axiom of every system of logic; dialethic logic exists. You might have doubts about its utility or its effectiveness -- relative to other logical options -- in dealing with the problems it is recruited to deal with, but that is another question.

Jobar

Gentlemen, I want to make clear that I have no *objection* to your discussion, in the least. I find it very interesting, and if you can come to some agreement on this subject I think it may qualify as a true advance of our philosophical understanding of nature and knowledge. My job as a mod here does require me to keep the conversations centered around the forum topic, and that is the reason I spoke up.

And, since this still has more to do with our theories of knowledge than with our theories of deities, I am moving this to Philosophy.

John Page

Science aside, can the universe itself not be considered as a perpetual motion machine? Is there data that contradicts this? What about 2LT and arguments for increase and decrease in entropy? If entropy is decreasing is everything just winding down to the end of time? If entropy is increasing is the universe still flinging itself apart? Does the current TOE (evolving, Popper-like) predict that entropy over the entire universe remains at the same overall level? If the answer to the latter is yes it would seem to me that under that TOE the universe is a perpetual motion machine. Just curious.

Cheers, John