Definite Description - Mathematical Logic

Mathematical Logic

In much formal work, authors use a definite description operator symbolized using . The operator is usually defined so as to reflect a Russellian analysis of descriptions (though other authors, especially in linguistics, use the operator with a Fregean semantics). Thus

,

means "the unique such that ", and

is stipulated to be equivalent to "There is exactly one and it has the property ":

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