6 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'! |
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. |
6456 | Sense-data are neutral uninterpreted experiences, separated from objects and judgements [Angeles] |
Full Idea: Sense-data are that which is given to us directly and immediately such as colour, shape, smell, without identification of them as specific material objects; they are usually thought to be devoid of judgment, interpretation, bias, preconception. | |
From: Peter A. Angeles (A Dictionary of Philosophy [1981], p.254) | |
A reaction: This definition makes them clearly mental (rather than being qualities of objects), and they sound like Hume's 'impressions'. They are not features of the external world, but the first steps we make towards experience. |
15877 | The aim of science is just to create a comprehensive, elegant language to describe brute facts [Poincaré, by Harré] |
Full Idea: In Poincaré's view, we try to construct a language within which the brute facts of experience are expressed as comprehensively and as elegantly as possible. The job of science is the forging of a language precisely suited to that purpose. | |
From: report of Henri Poincaré (The Value of Science [1906], Pt III) by Rom Harré - Laws of Nature 2 | |
A reaction: I'm often struck by how obscure and difficult our accounts of self-evident facts can be. Chairs are easy, and the metaphysics of chairs is hideous. Why is that? I'm a robust realist, but I like Poincaré's idea. He permits facts. |