||Possible worlds semantics is a general approach to theories of meaning, on which meanings (or, more precisely, semantic values) are assigned to sentences in terms of the truth-values they take across all possible worlds. The intuition is that the meaning of a sentence specifies how the world would have to be for that sentence to be true (or false). This is typically made precise by identifying the semantic value of a sentence with its possible-worlds intension, a function from possible worlds to truth-values. When those values are just true and false (and are mutually exclusive), possible worlds intensions are equivalent to sets of possible worlds (the worlds at which the sentence is question is true). The approach can be generalised by treating semantic values for sub-sentential items (such as nouns and verbs) as functions from possible worlds to other entities (such as particulars, properties and relations). ‘Possible worlds semantics’ is also used in a narrower sense, to refer to formal Kripke semantics for modal (and other) logics.