纽康难题是另一种囚犯困境吗?

Are Newcomb's Problem and Prisoners' Dilemma One and the Same Problem?

囚犯困境(Prisoner’s Dilemma)与纽康难题(Newcomb’s Problem)是决策理论中著名的两个难题。David Lewis(1979)论证了这两个难题其实是同一种问题。如果Lewis是对的,那么这两个难题会有同一种解决方案。JoséLuis Bermúdez(2013)反驳Lewis的论证,他指出Lewis忽略了纽康难题中玩家所面临的知态处境,在将此处境加入考虑之后,Lewis的论证将会失败。在这篇文章,笔者通过分析Bermúdez的论证,指出他的论证缺陷,进而修改他的论证,说明在做出适当的补充后,Bermúdez原来企图构造的论证才可能实现。最后,进一步说明,即使完成了Bermúdez心目中的论证,他的论证依然不足以成功反驳Lewis,也因此不足以证明囚犯困境与纽康难题是两种拥有不同结构的问题。

Prisoner5s Dilemma and Newcomb5s Problem are two famous problems in the field of decision theory. David Lewis （1979） argues that these two problems are actually one and the same problem. IfLewis is right, we can expect that these two problems have one and the same solution. But Jose Luis Bermudez （2013） argues against Lewis5s argument and indicates that Lewis5s argument ignores the epistemic situation of the player in New- comb5s Problem. Bermudez claims that adding the epistemic situation into consideration would undermine Lewis5s argument and prove that Prisoner5s Dilemma and Newcomb5s Problem are not the same problem. I disagree with Bermudez. In this paper, I first argue that Bermudez5s argument is incomplete. Moreover, I show that even after his argument is completed, it still cannot successfully refute Lewis’s argument. Therefore, Bermudez fails to show that these two problems are different.