Wei_Dai wrote on 19 August 2009 07:08:23AM :

... Omega's AIs will reason as follows: "I have 1/2 chance of playing against a TDT, and 1/2 chance of playing against a CDT. If I play C, then my opponent will play C if it's a TDT, and D if it's a CDT ...

That seems to violate the secrecy assumptions of the Prisoner's Dilemma problem! I thought each prisoner has to commit to his action before learning what the other one did. What am I missing?

Thanks!