Acausal Trade - LessWrong
In acausal trade, two agents each benefit by predicting what the other wants and doing it, even though they might have no way of communicating or affecting each other, nor even any direct evidence that the other exists. This concept emerged out of the much-debated question of how to achieve cooperation on a one-shot Prisoner's Dilemma, where, by design, the two players are not allowed to communicate. On the one hand, a player who is considering the causal consequences of a decision ("Causal Decision Theory") finds that defection always produces a better result. On the other hand, if the other player symmetrically reasons this way, the result is a Defect/Defect equilibrium, which is bad for both agents. If they could somehow converge on Cooperate, they would each individually do better. The question is what variation on decision theory would allow this beneficial equilibrium. Douglas Hofstadter (see references) coined the term "superrationality" to express this state of convergence. He
x Acausal Trade — LessWrong Acausal Trade Edited by JoshuaFox , et al. last updated 26th Jun 2025 In acausal trade , two agents each benefit by predicting what the other wants and doing it, even though they might have no way of communicating or affecting each other, nor even any direct evidence that the other exists. Background: Superrationality and the one-shot Prisoner's Dilemma This concept emerged out of the much-debated question of how to achieve cooperation on a one-shot Prisoner's Dilemma , where, by design, the two players are not allowed to communicate. On the one hand, a player who i
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