The prescriptions of our two most prominent strands of decision theory, evidential and causal, differ in a general class of problems known as Newcomb problems. In these, evidential decision theory prescribes choosing a dominated act. Attempts have been made at reconciling the two theories by relying on additional requirements such as ratification (Jeffrey 1983) or "tickles" (Eells 1982). It has been argued that such attempts have failed (Lewis 1981a; Skyrms 1982). More recently, Huttegger (forthcoming) has developed a version of deliberative decision theory that reconciles the prescriptions of the evidentialist and causalist. In this paper, I extend this framework to problems characterised by decision instability, and show that it cannot deliver a resolute answer under a plausible specification of the tickle. I prove that there exists a robust method of determining whether the specification of the tickle matters for all two-state, two-act problems whose payoff tables exhibit some basic mathematical relationships. One upshot is that we have a principled way of knowing ex-ante whether a reconciliation of evidential and causal decision theory is plausible for a wide range of decision problems under this framework. Another upshot is that the tickle approach needs further work to achieve full reconciliation.

翻译：我们最突出的两个决策理论流派——证据主义和因果主义——在被称为纽科姆问题的普遍问题类别中存在分歧。在这些问题中，证据决策理论建议选择被支配的行为。已有尝试通过依赖附加条件如批准（Jeffrey 1983）或“叮咬”（Eells 1982）来调和这两种理论。但已有论证表明这些尝试失败（Lewis 1981a; Skyrms 1982）。近期，Huttegger（即将发表）发展了一种审议决策理论的版本，调和了证据主义与因果主义的规定。本文将该框架扩展至以决策不稳定性为特征的问题，并证明在叮咬的合理设定下，该框架无法提供明确的答案。我证明了存在一种稳健方法，可确定对于所有满足基本数学关系的两状态两行动问题，叮咬的设定是否关键。其中一个结论是，在该框架下，我们拥有了先验判断证据决策理论与因果决策理论调和是否可能的原则性方法。另一个结论是，完全实现调和仍需进一步研究叮咬方法。