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In linguistic semantics, a generalized quantifier is an expression that denotes a property of a property, also called a higher-order property. This is the standard semantics assigned to quantified noun phrases, also called determiner phrases, or DP for short. In the example below, the DP ''every boy'' says of a property X that the set of entities that are ''boys'' is a subset of the set of entities that have property X. So the following sentence says that the set of boys is a subset of the set of sleepers. ::Every boy sleeps. :: This treatment of quantifiers has been essential in achieving a compositional semantics for sentences containing quantifiers.〔 Montague, Richard: 1974, '(The proper treatment of quantification in English )', in R. Montague, Formal Philosophy, ed. by R. Thomason (New Haven). 〕〔Barwise, Jon and Robin Cooper. 1981. Generalized quantifiers and natural language. ''Linguistics and Philosophy'' 4: 159-219.〕 ==Type theory== A version of type theory is often used to make the semantics of different kinds of expressions explicit. The standard construction defines the set of types recursively as follows: #''e'' and ''t'' are types. #If ''a'' and ''b'' are both types, then so is #Nothing is a type, except what can be constructed on the basis of lines 1 and 2 above. Given this definition, we have the simple types ''e'' and ''t'', but also a countable infinity of complex types, some of which include: :: *Expressions of type ''e'' denote elements of the universe of discourse, the set of entities the discourse is about. This set is usually written as . Examples of type ''e'' expressions include ''John'' and ''he''. *Expressions of type ''t'' denote a truth value, usually rendered as the set, where 0 stands for "false" and 1 stands for "true". Examples of expressions that are sometimes said to be of type ''t'' are ''sentences'' or ''propositions''. *Expressions of type denote functions from the set of entities to the set of truth values. This set of functions is rendered as . Such functions are characteristic functions of sets. They map every individual that is an element of the set to "true", and everything else to "false." It is common to say that they denote ''sets'' rather than characteristic functions, although, strictly speaking, the latter is more accurate. Examples of expressions of this type are predicates, nouns and some kinds of adjectives. *In general, expressions of complex types denote functions from the set of entities of type to the set of entities of type , a construct we can write as follows: . We can now assign types to the words in our sentence above (Every boy sleeps) as follows. * *Type(boy)= * *Type(sleeps)= * *Type(every)= Thus, every denotes a function from a ''set'' to a function from a set to a truth value. Put differently, it denotes a function from a set to a set of sets. It is that function which for any two sets ''A,B'', ''every''(''A'')(''B'')= 1 if and only if . 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「generalized quantifier」の詳細全文を読む スポンサード リンク
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