Abstract It is a widely held principle that no one is able to do something that would require the past to have been different from how it actually is. This principle of the fixity of the past has been presented in numerous ways, playing a crucial role in arguments for logical and theological fatalism, and for the incompatibility of causal determinism and the ability to do otherwise. I will argue that, assuming bivalence, this principle is in conflict with standard views about knowledge and the semantics for ‘actually’. I also consider many possible responses to the argument.

中文翻译：

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关于过去的固定性的谜题

摘要 一个被广泛接受的原则是，没有人能够做一些需要过去与实际情况不同的事情。过去的固定性原则已经以多种方式呈现，在逻辑和神学宿命论的论证中，以及因果决定论的不相容性和其他方面的能力方面发挥着至关重要的作用。我将争辩说，假设二价，这一原则与关于知识的标准观点和“实际上”的语义相冲突。我还考虑了对该论点的许多可能的回应。