RobinZ comments on Belief in Belief - Less Wrong

66 Post author: Eliezer_Yudkowsky 29 July 2007 05:49PM

You are viewing a comment permalink. View the original post to see all comments and the full post content.

Comments (164)

Sort By: Old

You are viewing a single comment's thread. Show more comments above.

Comment author: Quarkster 29 November 2009 02:50:06AM 4 points [-]

"Those who find this confusing may find it helpful to study mathematical logic, which trains one to make very sharp distinctions between the proposition P, a proof of P, and a proof that P is provable"

This is a bit of a side question, but wouldn't a proof that P is provable be a proof of P? In fact, it sounds like a particularly elegant form of proof.

Comment author: RobinZ 29 November 2009 02:53:42AM 1 point [-]

Seconded - this is an interesting question. (And I suspect that there are some interesting cases in which a proof that P is provable does not constitute a proof, but this is mainly because I've seen mathematicians break similarly intuitive propositions before.)

Comment author: wedrifid 29 November 2009 03:11:15AM 1 point [-]

I suspect that there are some interesting cases in which a proof that P is provable does not constitute a proof, but this is mainly because I've seen mathematicians break similarly intuitive propositions before.

It wouldn't surprise me either. However such cases would have to rely on a precise definition of 'proof' differently to what I use. The result would then be filed under 'fascinating technical example' but not under 'startling revelation' and I would take note of the jargon for use when talking to other mathematicians.