CannibalSmith comments on The Aumann's agreement theorem game (guess 2/3 of the average) - Less Wrong
You are viewing a comment permalink. View the original post to see all comments and the full post content.
You are viewing a comment permalink. View the original post to see all comments and the full post content.
Comments (149)
Naively appealing, but if the third step is "so you'll pick 44 instead", the first step claiming that "You will pick 100, and I know that" is incorrect.
Okay.
You will pick X - a number whose value I don't know. I know that, so I'll pick X*2/3. You know that I know that, so you'll pick X*4/9 instead. But I know that you know that I know that, so I'll pick X*8/27 instead. But you know that I know that you know that I know that, so you'll pick X*16/81 instead. But I know-
This continues to infinity until X is multiplied by 0. At this point the value of X doesn't matter.
Nope, it's the same argument. You can't know that I pick X and at the same time know that I pick X*4/9 instead. From the outset, you can't assume to know precisely what I pick, and considering all possible values that I pick and you know I pick (a set of situations indexed by X) doesn't fix that.