| 释义 |
extensionality Philos.|ɛkstɛnʃəˈnælɪtɪ|
[f. extensional a. + -ity.]
The state or fact of being extensional (see prec.). So thesis of extensionality (see quot. 1956).
1926F. P. Ramsey in Proc. London Math. Soc. XXV. 348 The difficulties of the tautology theory..spring from a fundamental characteristic of modern analysis which..may be called extensionality, and the difficulties may be explained as those which confront us if we try to reduce a calculus of extensions to a calculus of truth-functions. 1937A. Smeaton tr. Carnap's Logical Syntax Lang. iv. §67. 245 The Thesis of Extensionality. Wittgenstein..put forward the thesis that every sentence is ‘a truth-function of the elementary sentences’ and therefore (in our terminology) extensional in relation to partial sentences. 1944K. Gödel in P. A. Schilpp Philos. B. Russell 137 The axiom of extensionality (i.e., that no two different properties belong to exactly the same things). 1956J. O. Urmson Philos. Analysis i. ii. 12 This thesis that language is throughout truth-functional was often called the thesis of extensionality. Every statement anyone ever makes must, according to this thesis.., be either a logically simple statement or else a truth-function of such statements. |