Tetronian comments on two puzzles on rationality of defeat - Less Wrong

4 Post author: fsopho 12 December 2011 02:17PM

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

Comments (55)

You are viewing a single comment's thread.

Comment author: [deleted] 12 December 2011 02:54:53PM *  4 points [-]

Both of these puzzles fall apart if you understand the concepts in Argument Screens Off Authority, A Priori, and Bayes Theorem. Essentially, the notion of "defeat" is extremely silly. In Puzzle 1, for example, what you should really be doing is updating your level of belief in T based on the mathematician's argument. The order in which you heard the arguments doesn't matter--the two Bayesian updates will still give you the same posterior regardless of which one you update on first.

Puzzle 2 is similarly confused about "defeat"; the notion of "misleading evidence" in Puzzle 2 is also wrong. If you look at things in terms of probabilities instead of the "known/not known" dichotomy presented in the puzzle, there is no confusion. Just update on the mathematician's argument and be done with it.

Comment author: fsopho 12 December 2011 05:39:42PM -1 points [-]

Well, puzzle 2 is a puzzle with a case of knowledge: I know (T). Changing to probabilities does not solve the problem, only changes it!

Comment author: [deleted] 12 December 2011 06:10:03PM 4 points [-]

But that's the thing: you don't "know" (T). You have a certain degree of belief, which is represented by a real number between 1 and 0, that (T) is true. You can then update this degree of belief based on (RM) and (TM).