6 ideas
18261 | A simplification which is complete constitutes a definition [Kant] |
Full Idea: By dissection I can make the concept distinct only by making the marks it contains clear. That is what analysis does. If this analysis is complete ...and in addition there are not so many marks, then it is precise and so constitutes a definition. | |
From: Immanuel Kant (Wiener Logik [1795], p.455), quoted by J. Alberto Coffa - The Semantic Tradition from Kant to Carnap 1 'Conc' | |
A reaction: I think Aristotle would approve of this. We need to grasp that a philosophical definition is quite different from a lexicographical definition. 'Completeness' may involve quite a lot. |
9616 | A set is a collection into a whole of distinct objects of our intuition or thought [Cantor] |
Full Idea: A set is any collection into a whole M of definite, distinct objects m ... of our intuition or thought. | |
From: George Cantor (The Theory of Transfinite Numbers [1897], p.85), quoted by James Robert Brown - Philosophy of Mathematics Ch.2 | |
A reaction: This is the original conception of a set, which hit trouble with Russell's Paradox. Cantor's original definition immediately invites thoughts about the status of vague objects. |
22275 | Logic gives us the necessary rules which show us how we ought to think [Kant] |
Full Idea: In logic the question is not one of contingent but of necessary rules, not how to think, but how we ought to think. | |
From: Immanuel Kant (Wiener Logik [1795], p.16), quoted by Michael Potter - The Rise of Analytic Philosophy 1879-1930 02 'Trans' | |
A reaction: Presumably it aspires to the objectivity of a single correct account of how we all ought to think. I'm sympathetic to that, rather than modern cultural relativism about reason. Logic is rooted in nature, not in arbitrary convention. |
15896 | Cantor needed Power Set for the reals, but then couldn't count the new collections [Cantor, by Lavine] |
Full Idea: Cantor grafted the Power Set axiom onto his theory when he needed it to incorporate the real numbers, ...but his theory was supposed to be theory of collections that can be counted, but he didn't know how to count the new collections. | |
From: report of George Cantor (The Theory of Transfinite Numbers [1897]) by Shaughan Lavine - Understanding the Infinite I | |
A reaction: I take this to refer to the countability of the sets, rather than the members of the sets. Lavine notes that counting was Cantor's key principle, but he now had to abandon it. Zermelo came to the rescue. |
18260 | If we knew what we know, we would be astonished [Kant] |
Full Idea: If we only know what we know ...we would be astonished by the treasures contained in our knowledge. | |
From: Immanuel Kant (Wiener Logik [1795], p.843), quoted by J. Alberto Coffa - The Semantic Tradition from Kant to Carnap 1 'Conc' | |
A reaction: Nice remark. He doesn't require immediat recall of knowledge. You can't be required to know that you know something. That doesn't imply externalism, though. I believe in securely founded internal knowledge which is hard to recall. |
16707 | Cold and hot are the swiftness and slowness of corpuscular motion [Beeckman] |
Full Idea: There is no doubt that the nature of cold and hot are taken from the swiftness and slowness of the motion of corpuscules. | |
From: Isaac Beeckman (Journals [1617], I:132), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 19.6 | |
A reaction: This is so right it takes your breath away. For 'corpuscles' we should normally read 'molecules'. Atomism is a further refinement. This is the rejection of the orthodox view of separate qualities. |