Allan: There are benefits and no costs to defecting.
This is the same error as in the Newcomb’s problem: there is in fact a cost. In case of prisoner’s dilemma, you are penalized by ending up with (D,D) instead of better (C,C) for deciding to defect, and in the case of Newcomb’s problem you are penalized by having only $1000 instead of $1,000,000 for deciding to take both boxes.
Allan: There are benefits and no costs to defecting.
This is the same error as in the Newcomb’s problem: there is in fact a cost. In case of prisoner’s dilemma, you are penalized by ending up with (D,D) instead of better (C,C) for deciding to defect, and in the case of Newcomb’s problem you are penalized by having only $1000 instead of $1,000,000 for deciding to take both boxes.