You're looking at Less Wrong's discussion board. This includes all posts, including those that haven't been promoted to the front page yet. For more information, see About Less Wrong.

Randaly comments on Can anyone explain to me why CDT two-boxes? - Less Wrong Discussion

-12 Post author: Andreas_Giger 02 July 2012 06:06AM

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

Comments (136)

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

Comment author: Randaly 02 July 2012 02:20:56PM 1 point [-]

No, this is false. CDT is the one using the standard payoff matrix, and you are the one refusing to use the standard payoff matrix and substituting your own.

In particular: the money is either already there, or not already there. Once the game has begun, the Predictor is powerless to change things.

The standard payoff matrix for Newcomb is therefore as follows:

  • Omega predicts you take two boxes, you take two boxes, you get $n>0.
  • Omega predicts you take two boxes, you take two boxes, you get 0.
  • Omega predicts you take one box, you take one box, you get $m>n.
  • Omega predicts you take one box, you take two boxes, you get $m+n>m.

The problem becomes trivial if, as you are doing, you refuse to consider the second and fourth outcomes. However, you are then not playing Newcomb's Problem.

Comment author: Andreas_Giger 02 July 2012 02:52:07PM -2 points [-]

No, only then am I playing Newcomb. What you're playing is weak Newcomb, where you assign a probability of x>0 for Omega being wrong, at which point this becomes simple math where CDT will give you the correct result, whatever that may turn out to be.

Comment author: Randaly 02 July 2012 03:10:40PM 2 points [-]

No, you are assuming that your decision can change what's in the box, which everybody agrees is wrong: the problem statement is that you cannot change what's in the million-dollar box.

Also, what you describe as "weak Newcomb" is the standard formulation: Nozick's original problem stated that the Predictor was "almost always" right. CDT still gives the wrong answer in simple Newcomb, as its decision cannot affect what's in the box.