11 ideas
| 12430 | Classical logic is our preconditions for assessing empirical evidence [Kitcher] |
| Full Idea: In my terminology, classical logic (or at least, its most central tenets) consists of propositional preconditions for our assessing empirical evidence in the way we do. | |
| From: Philip Kitcher (A Priori Knowledge Revisited [2000], §VII) | |
| A reaction: I like an even stronger version of this - that classical logic arises out of our experiences of things, and so we are just assessing empirical evidence in terms of other (generalised) empirical evidence. Logic results from induction. Very unfashionable. |
| 12431 | I believe classical logic because I was taught it and use it, but it could be undermined [Kitcher] |
| Full Idea: I believe the laws of classical logic, in part because I was taught them, and in part because I think I see how those laws are used in assessing evidence. But my belief could easily be undermined by experience. | |
| From: Philip Kitcher (A Priori Knowledge Revisited [2000], §VII) | |
| A reaction: Quine has one genuine follower! The trouble is his first sentence would fit witch-doctoring just as well. Kitcher went to Cambridge; I hope he doesn't just believe things because he was taught them, or because he 'sees how they are used'! |
| 17505 | Using proper names properly doesn't involve necessary and sufficient conditions [Putnam] |
| Full Idea: The important thing about proper names is that it would be ridiculous to think that having linguistic competence can be equated in their case with knowledge of a necessary and sufficient condition. | |
| From: Hilary Putnam (Explanation and Reference [1973], II B) |
| 10245 | One geometry cannot be more true than another [Poincaré] |
| Full Idea: One geometry cannot be more true than another; it can only be more convenient. | |
| From: Henri Poincaré (Science and Method [1908], p.65), quoted by Stewart Shapiro - Philosophy of Mathematics | |
| A reaction: This is the culminating view after new geometries were developed by tinkering with Euclid's parallels postulate. |
| 11908 | Putnam bases essences on 'same kind', but same kinds may not share properties [Mackie,P on Putnam] |
| Full Idea: The only place for essentialism to come from in Putnam's semantic account is out of the 'same kind' relation. But if the same kind relation can be cashed out in terms that do not involve sharing properties (apart from 'being water') there is a gap. | |
| From: comment on Hilary Putnam (Explanation and Reference [1973]) by Penelope Mackie - How Things Might Have Been 10.4 | |
| A reaction: [This is the criticism of Salmon and Mellor] See Mackie's discussion for details. I would always have thought that relations result from essences, so could never be used to define them. |
| 12428 | Many necessities are inexpressible, and unknowable a priori [Kitcher] |
| Full Idea: There are plenty of necessary truths that we are unable to express, let alone know a priori. | |
| From: Philip Kitcher (A Priori Knowledge Revisited [2000], §II) | |
| A reaction: This certainly seems to put paid to any simplistic idea that the a priori and the necessary are totally coextensive. We might, I suppose, claim that all necessities are a priori for the Archangel Gabriel (or even a very bright cherub). Cf. Idea 12429. |
| 12429 | Knowing our own existence is a priori, but not necessary [Kitcher] |
| Full Idea: What is known a priori may not be necessary, if we know a priori that we ourselves exist and are actual. | |
| From: Philip Kitcher (A Priori Knowledge Revisited [2000], §II) | |
| A reaction: Compare Idea 12428, which challenges the inverse of this relationship. This one looks equally convincing, and Kripke adds other examples of contingent a priori truths, such as those referring to the metre rule in Paris. |
| 17508 | Science aims at truth, not at 'simplicity' [Putnam] |
| Full Idea: Scientists are not trying to maximise some formal property of 'simplicity'; they are trying to maximise truth. | |
| From: Hilary Putnam (Explanation and Reference [1973], III B) | |
| A reaction: This seems to be aimed at the Mill-Ramsey-Lewis account of laws of nature, as the simplest axioms of experience. I'm with Putnam (as he was at this date). |
| 17506 | I now think reference by the tests of experts is a special case of being causally connected [Putnam] |
| Full Idea: In previous papers I suggested that the reference is fixed by a test known to experts; it now seems to me that this is just a special case of my use being causally connected to an introducing event. | |
| From: Hilary Putnam (Explanation and Reference [1973], II C) | |
| A reaction: I think he was probably right the first time, and has now wandered off course. |
| 17507 | Natural kind stereotypes are 'strong' (obvious, like tiger) or 'weak' (obscure, like molybdenum) [Putnam] |
| Full Idea: Natural kinds can be associated with 'strong' stereotypes (giving a strong picture of a typical member, like a tiger), or with 'weak' stereotypes (with no idea of a sufficient condition, such as molybdenum or elm). | |
| From: Hilary Putnam (Explanation and Reference [1973], II C) |
| 11904 | Express natural kinds as a posteriori predicate connections, not as singular terms [Putnam, by Mackie,P] |
| Full Idea: Putnam implies dispensing with the designation of natural kinds by singular terms in favour of the postulation of necessary but a posteriori connections between predicates. ...We might call this 'predicate essentialism', but not 'de re essentialism'. | |
| From: report of Hilary Putnam (Explanation and Reference [1973]) by Penelope Mackie - How Things Might Have Been 10.1 | |
| A reaction: It is characteristic of modern discussion that the logical form of natural kind statements is held to be crucial, rather than an account of nature in any old ways that do the job. So do I prefer singular terms, or predicate-connections. Hm. |