display all the ideas for this combination of texts
5 ideas
3332 | Greeks saw the science of proportion as the link between geometry and arithmetic [Benardete,JA] |
Full Idea: The Greeks saw the independent science of proportion as the link between geometry and arithmetic. | |
From: José A. Benardete (Metaphysics: the logical approach [1989], Ch.15) |
3330 | Negatives, rationals, irrationals and imaginaries are all postulated to solve baffling equations [Benardete,JA] |
Full Idea: The Negative numbers are postulated (magic word) to solve x=5-8, Rationals postulated to solve 2x=3, Irrationals for x-squared=2, and Imaginaries for x-squared=-1. (…and Zero for x=5-5) …and x/0 remains eternally open. | |
From: José A. Benardete (Metaphysics: the logical approach [1989], Ch.14) |
3337 | Natural numbers are seen in terms of either their ordinality (Peano), or cardinality (set theory) [Benardete,JA] |
Full Idea: One approaches the natural numbers in terms of either their ordinality (Peano), or cardinality (set theory). | |
From: José A. Benardete (Metaphysics: the logical approach [1989], Ch.17) |
10833 | Many concepts can only be expressed by second-order logic [Boolos] |
Full Idea: The notions of infinity and countability can be characterized by second-order sentences, though not by first-order sentences (as compactness and Skolem-Löwenheim theorems show), .. as well as well-ordering, progression, ancestral and identity. | |
From: George Boolos (On Second-Order Logic [1975], p.48) |
21570 | Numbers are just verbal conveniences, which can be analysed away [Russell] |
Full Idea: Numbers are nothing but a verbal convenience, and disappear when the propositions that seem to contain them are fully written out. | |
From: Bertrand Russell (Is Mathematics purely Linguistic? [1952], p.301) | |
A reaction: This is the culmination of the process which began with his 1905 theory of definite descriptions. The intervening step was Wittgenstein's purely formal account of the logical connectives. |