Originally posted by scottishinnz
Okay, I see your point, provided you are working only using a hypothesis / null hypothesis pair. Most people are not, however.

My claim is not limited to the realm of hypothesis testing.

What alternative framework might somebody employ in which my claim does not hold? That is, in what sort of framework is it actually the case that a proof of P does not immediately yield a proof of Not-(Not-P)?

For example, suppose somebody is deliberating on the color of roses, and somehow proves "P: Roses are red". In what sort of framework for deliberation would one not be able to validly deduce "Not-(Not-P): It is not the case that roses are not red"? Certainly not a very useful one, because it would have to reject the notion of the logical operator Not, which is fundamental to logical reasoning and without which you will have propositions that are both true and false, which would defeat the very purpose of the truth-seeking framework.

Originally posted by DoctorScribbles
My claim is not limited to the realm of hypothesis testing.

What alternative framework might somebody employ in which my claim does not hold? That is, in what sort of framework is it actually the case that a proof of P does not immediately yield a proof of Not-(Not-P)?

For example, suppose somebody is deliberating on the color of roses, and so ...[text shortened]... "Not-(Not-P): It is not the case that roses are not red"? Certainly not a very useful one.

In some cases we have two (and only 2) possible, logical choices , P and Q. By proving that P isn't true, we can make the logical deduction that since Pis not right, Q must, in fact, be the true answer.

Kind of like the 50:50 option on "who wants to be a millionaire".

Originally posted by scottishinnz
In some cases we have two (and only 2) possible, logical choices , P and Q. By proving that P isn't true, we can make the logical deduction that since Pis not right, Q must, in fact, be the true answer.

Kind of like the 50:50 option on "who wants to be a millionaire".

Not in some cases.

In all cases such a Q exists, namely, Not-P. That is the very point, and one of the many reasons why "you can't prove a negative" is so gratingly ridiculous.

If you deny this, please provide a counterexample. That is, construct a P such that P is true while Not-(Not-P) is false.

Originally posted by twhitehead
It depends on what you mean by 'proof'. I know what it means in mathematics but it gets a bit vague when used anywhere else.
However, by any normal understanding of the word, it is perfectly possible to prove that some things do not exist. For example:
A block of solid Iron 20cm x 20cm situated in the center of your brain does not exist. Do you really n ...[text shortened]... o accept the existence of such rocks and will go to great lengths to justify their denial.

the difference is that you could open a brain and observe that there is no block in there. you can not observe the entire solar system and say that you didnt see god anywhere.

Originally posted by DoctorScribbles
Not in some cases.

In all cases such a Q exists, namely, Not-P. That is the very point, and one of the many reasons why "you can't prove a negative" is so gratingly ridiculous.

If you deny this, please provide a counterexample. That is, construct a P such that P is true while Not-(Not-P) is false.

I don't deny your example, P and not-P. I concede the point. I had a proverbial brainfart. Thank you for your words.

However, in the case of God, it would seem we are unable to prove his existence, i.e. P is unknown, therefore we cannot make any decision, i.e. not-P is unknown.

Originally posted by josephw
My question is, how can you be sure that a human being can't rise from the dead?

By definition:
1. Human Being: A non-supernatural organism.
2. Dead: A state which it is impossible to rise from.
It would be a violation of the known laws of physics, biology etc etc. If he did 'rise from the dead' then he either wasn't dead or was no longer a human being or at the very least not the same human being as there must have been a discontinuity of the relevant atoms etc.

But all that is just me having fun. The real answer to your question is:
I cannot be sure. It would be a supernatural event. I cannot be sure that supernatural events do not take place, but as a scientist I am yet to see any convincing evidence that any single supernatural event has ever been observed in the history of mankind. If they do occur, then they either have an exceedingly small effect on the universe or they are designed in such a way as to be virtually undetectable.

Originally posted by EcstremeVenom
the difference is that you could open a brain and observe that there is no block in there. you can not observe the entire solar system and say that you didnt see god anywhere.

As I said, it depends on your definition of God. If your god is a little green bunny on a minor planet orbiting a star in a galaxy far far away, then no, I cannot prove that he doesn't exist. However, it is false to then proceed to claim that I cannot prove the non-existence of God whatever the definition. In most cases I should only be unable to prove his non-existence if one of the following is true:
1. The definition given is so vague as to be essentially meaningless.
2. The definition applies to an entity that does not affect me in any significant manner. (such as the green bunny scenario).
3. The definition applies to an entity that makes itself undetectable via supernatural means. eg it modifies the results of my experiments to avoid detection.

Originally posted by DoctorScribbles
For such a retarded comment, it sure gets made in this forum with astounding frequency.

For any proposition P, Not-(Not-P) has an equivalent truth value. Therefore, anytime you prove P, you necessarily prove Not-(Not-P). Thus, every time any assertion at all is proven, a negative assertion is necessarily proven to be true as a consequence.

Si ...[text shortened]... the solution and not part of the problem, and cease further invocations of this asinine slogan.

WOW!

Originally posted by rwingett
It doesn't matter. There could be any number of answers. But if you disprove P then you've proven not-P. That may not tell you what the right answer is, but it will tell you that P isn't it.

What?

Originally posted by DoctorScribbles
Don't be stupid. Regarding the truth value of P, only two possibilities do exist: true, or false. Similarly, only two complementary possibilities exist for the truth value of Not-P: false, or true.

Proving or disproving P always has bearing on the truth values of an infinitude of other propositions. Case in point, proof of P necessarily yields a proof of Not-(Not-P). Do you actually deny this?

Ouch!

Originally posted by scottishinnz
Okay, I see your point, provided you are working only using a hypothesis / null hypothesis pair. Most people are not, however.

Despite this, there is no need to be rude about it - unless questions are not allowed?

OH!

Originally posted by DoctorScribbles
My claim is not limited to the realm of hypothesis testing.

What alternative framework might somebody employ in which my claim does not hold? That is, in what sort of framework is it actually the case that a proof of P does not immediately yield a proof of Not-(Not-P)?

For example, suppose somebody is deliberating on the color of roses, and so ...[text shortened]... are both true and false, which would defeat the very purpose of the truth-seeking framework.

Jeez.

Originally posted by scottishinnz
I don't deny your example, P and not-P. I concede the point. I had a proverbial brainfart. Thank you for your words.

However, in the case of God, it would seem we are unable to prove his existence, i.e. P is unknown, therefore we cannot make any decision, i.e. not-P is unknown.

No wonder!

Originally posted by DoctorScribbles
Not in some cases.

In all cases such a Q exists, namely, Not-P. That is the very point, and one of the many reasons why "you can't prove a negative" is so gratingly ridiculous.

If you deny this, please provide a counterexample. That is, construct a P such that P is true while Not-(Not-P) is false.

Hmm, in hindsight, I think we were talking at slight odds to each other. You discuss only a hypothesis / null hypothesis pair. P and not-P. However, Q, R, W and Z are all, also, not-P. If we want to ask the really dull question of whether something exists or not, I agree you are right. If we have many non-P options to choose amongst a simple P / not-P hypothesis / null hypothesis pair is of limited value.

Trying to disprove the existence of God is more like the second one, because the goalposts of what God is are so poorly defined.

Originally posted by josephw
My question is, how can you be sure that a human being can't rise from the dead?

God damn boy, if that's the extent of your argument, you are in some serious discussion doo doo.