Comment by dragonwriter | Hacker News Reader

Comment by dragonwriter | Hacker News Reader

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> There are tight logical proofs.

No, there aren't.

> Note I point out the ontological argument is now validated by computer.

While an invalid argument is useless, a valid one can still be no good.

Here is a logically valid argument:

Major Premise. all who post claims of proofs of God’s existence on HN should be killed.

Minor Premise. yters posted a claim of proof of God’s existence on HN

Conclusion. Therefore, yters should be killed.

Now, if I claimed I proved you should be killed, you would probably object, and claim there was a problem with the major premise. And I think many people would agree with you, but the correctness of the premises isn't relevant to logical validity, only soundness.

Well that's the problem with all proofs. If the premises are false the proof is not sound. That doesn't preclude the proof being tight, i.e. as in well reasoned and logically argued. Outside of mathematics you will be hard pressed to find a proof where someone doesn't disagree with a premise or two. And even within math we have intuitionists and constructivists claiming things like proof by negation is invalid. So if your criterion for solid proof is one that everyone agrees with, you are bound to be perpetually disappointed. On the other hand if your criterion is proofs that highly intelligent people find convincing after fully understanding the argument, then I again submit to you the ontological argument which even Russell claimed was sound at one point in his life before walking that back and saying it is wrong for some unknown reason.

> Well that's the problem with all proofs

No, its the problem with pure logical proofs, which is why for statements about reality rather than abstract relations of concepts, empirical proofs (despite being less absolute) are generally preferred.

> the ontological argument

Since you have merely waved at and sketched the argument, let me do the same it's demolition: existence is not a predicate.

I guess that means we cannot say anything exists. Sounds sensible to me.

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