While knowledge of mere possibilities is difficult to understand, knowledge of possibilities that are actual seems unproblematic (as far as we know the actual world). The principle that what is actual is possible has been near-universally accepted. After summarizing some sporadic dissent, I present a proposal for how the validity of the principle might be restricted. While the principle certainly holds for sufficiently inclusive objective and epistemic possibilities, it may not hold when the accessibility of possibilities is contextually restricted.

中文翻译：

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Ab Esse ad Posse 非代客后果

虽然关于纯粹可能性的知识很难理解，但关于实际可能性的知识似乎没有问题（就我们所知的现实世界而言）。现实即可能的原则几乎已被普遍接受。在总结了一些零星的异议之后，我提出了如何限制该原则有效性的建议。虽然该原则确实适用于足够包容的客观和认知可能性，但当可能性的可及性受到上下文限制时，它可能不成立。