| 释义 |
impredicative, a.|ɪmˈprɛdɪkətɪv|
[f. im-2 + predicative a.]
Of a proposition, thing, etc.: not definable except in terms of a totality of which it is itself a part. Hence imˈpredicatively adv.; impredicaˈtivity, the state or quality of being impredicative.
1937A. Smeaton tr. Carnap's Logical Syntax of Lang. iv. §44. 162 A thing is usually called impredicative (in the material mode of speech) when it is defined (or can only be defined) with the help of a totality to which it itself belongs. 1944K. Gödel in P. A. Schilpp Philos. B. Russell ii. iii. 138 What an impredicative definition would require is to construct a notion by a combination of a set of notions to which the notion to be formed itself belongs. 1963W. V. Quine Set Theory §34. 242 He [sc. Poincaré] called the suspect procedure impredicative. 1965C. D. Parsons in M. Black Philos. in Amer. 196 Such extensions..allow impredicatively defined classes. Ibid. 197 This can only be because the mathematics itself involves impredicativity. |