You find yourself in a PD against a perfect copy of yourself. At the end of the game, I will remove the money your clone wins, destroy all records of what you did, re-merge you with your clone, erase both our memories of the process, and let you keep the money that you won (you will think it is just a gift to recompense you for sleeping in my lab for a few hours). You had not previously considered this situation possible, and had made no precommitments about what to do in such a scenario. What do you think you should do?
Given that you’re going to erase my memory of this conversation and burn a lot of other records afterward, it’s entirely possible that you’re lying about whether it’s me or the other me whose payout ‘actually counts.’ Makes no difference to you either way, right? We all look the same, and telling us different stories about the upcoming game would break the assumption of symmetry. Effectively, I’m playing a game of PD followed by a special step in which you flip a fair coin and, on heads, swap my reward with that of the other player.
So, I’d optimize for the combined reward to both myself and my clone, which is to say, for the usual PD payoff matrix, cooperate. If the reward for defecting when the other player cooperates is going to be worth drastically more to my postgame gestalt, to the point that I’d accept a 25% or less chance of that payout in trade for virtual certainty of the payout for mutual cooperation, I would instead behave randomly.
That they either must both hear the same story or else break the assumption of symmetry is an important objection to the hypothetical. Either choice breaks the problem statement as presented.
Thank you! If I was the other clone and heard that I was about to play a game of PD which would have no consequences for anyone except the other player, who was also me, that would distort my incentives.
It’s established in the problem statement that the experimenter is going to destroy or falsify all records of what transpired during the game, including the fact that a game even took place, presumably to rule out cooperation motivated by reputational effects. If you want a perfectly honest and trustworthy experimenter, establish that axiomatically, or at least don’t establish anything that directly contradicts.
Assuming that the other party is a clone with identical starting mind-state makes it a much more tractable problem. I don’t have much idea how perfect reasoners behave; I’ve never met one.
Given that you’re going to erase my memory of this conversation and burn a lot of other records afterward, it’s entirely possible that you’re lying about whether it’s me or the other me whose payout ‘actually counts.’ Makes no difference to you either way, right? We all look the same, and telling us different stories about the upcoming game would break the assumption of symmetry. Effectively, I’m playing a game of PD followed by a special step in which you flip a fair coin and, on heads, swap my reward with that of the other player.
So, I’d optimize for the combined reward to both myself and my clone, which is to say, for the usual PD payoff matrix, cooperate. If the reward for defecting when the other player cooperates is going to be worth drastically more to my postgame gestalt, to the point that I’d accept a 25% or less chance of that payout in trade for virtual certainty of the payout for mutual cooperation, I would instead behave randomly.
Saying “I wouldn’t trust someone like that to tell the truth about whose payout counts” is fighting the hypothetical.
I don’t think you need to assume the other party is a clone; you just need to assume that both you and the other party are perfect reasoners.
That they either must both hear the same story or else break the assumption of symmetry is an important objection to the hypothetical. Either choice breaks the problem statement as presented.
Thank you! If I was the other clone and heard that I was about to play a game of PD which would have no consequences for anyone except the other player, who was also me, that would distort my incentives.
It’s established in the problem statement that the experimenter is going to destroy or falsify all records of what transpired during the game, including the fact that a game even took place, presumably to rule out cooperation motivated by reputational effects. If you want a perfectly honest and trustworthy experimenter, establish that axiomatically, or at least don’t establish anything that directly contradicts.
Assuming that the other party is a clone with identical starting mind-state makes it a much more tractable problem. I don’t have much idea how perfect reasoners behave; I’ve never met one.