It is widely accepted that when “might” expresses certain kinds of relative modality, the sentence “p and it might not be the case that p” is in some sense inconsistent. It has proven difficult to define a formal semantics that explicates this inconsistency while meeting certain other desiderata, in particular, that p does not imply “Must p.” This paper presents such a semantics. The key idea is that background contexts have to have multiple levels, including an inner set consisting of worlds that represent what might be true and an outer set of worlds such that a sentence must be true only if it is true in all of them.

中文翻译：

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一个严格的强亲属必须

人们普遍认为，当“might”表达某种相对情态时，句子“ p and it may not be the case of the p ”在某种意义上是不一致的。已经证明很难定义一种形式语义来解释这种不一致，同时满足某些其他需求，特别是p并不意味着“必须p”。本文提出了这样的语义。关键思想是背景上下文必须有多个层次，包括一个由代表什么可能为真的世界组成的内部集合和一个外部世界集合，这样一个句子只有在所有这些都为真时才必须为真。