| 599 | We may have to postulate unobservable and unknowable substances [Aristotle] |
| Full Idea: It may well be necessary that certain unobserved substances exist as it is, even if we cannot know which they are. | |
| From: Aristotle (Metaphysics [c.324 BCE], 1041a02) |
| 16629 | By comparing qualities and features, reason can gradually infer the nature of substance [Grosseteste] |
| Full Idea: Awakened reason distinguishes color from size and shape from body and then shape and size from the substance of body, and so by drawing distinctions and abstracting, it arrives at a grasp of the substance of body, which supports size, shape and color. | |
| From: Robert Grosseteste (Commentary on 'Posterior Analytics' [1226], I.14), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 07.4 | |
| A reaction: This optimistic view influenced Aquinas, and is called 'incrementalism' by Pasnau. It is the spirit of scientific essentialism, and a nice instance of inference to the best explanation (though 'substance' in itself explains virtually nothing). |
| 5639 | Spinoza implies that thought is impossible without the notion of substance [Spinoza, by Scruton] |
| Full Idea: Without the notion of substance, according to Spinoza, thought itself becomes impossible. | |
| From: report of Baruch de Spinoza (The Ethics [1675]) by Roger Scruton - Short History of Modern Philosophy §5.2 | |
| A reaction: Spinoza's strategy here looks like the right way to approach metaphysics. To what extent is it possible to change our conceptual scheme? Quine seems to imply that there is no limit; Davidson seems to imply that it is impossible. |
| 12704 | Aggregates don’t reduce to points, or atoms, or illusion, so must reduce to substance [Leibniz] |
| Full Idea: In aggregates one must necessarily arrive either at mathematical points from which some make up extension, or at atoms (which I dismiss), or else no reality can be found in bodies, or finally one must recognises substances that possess a true unity. | |
| From: Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1687.04.30), quoted by Daniel Garber - Leibniz:Body,Substance,Monad 2 | |
| A reaction: Garber calls this Leibniz's Aggregate Argument. Leibniz is, of course, talking of physical aggregates which have unity. He consistently points out that a pile of logs has no unity at all. But is substance just that-which-provides-unity? |
| 10710 | We accept substance, to avoid infinite backwards chains of meaning [Wittgenstein, by Potter] |
| Full Idea: Wittgenstein is the most renowned modern proponent of substance, and argued that sense must be determinate ...and that any conceptual scheme which genuinely represents a world cannot contain infinite backward chains of meaning. | |
| From: report of Ludwig Wittgenstein (works [1935]) by Michael Potter - Set Theory and Its Philosophy 03.3 | |
| A reaction: This is a key idea for explaining the somewhat surprising revival of the notion of substance in modern times, when it appeared to have been buried by atomism in the seventeenth century. The new argument is a semantic one. |
| 13042 | If dependence is well-founded, with no infinite backward chains, this implies substances [Potter] |
| Full Idea: The argument that the relation of dependence is well-founded ...is a version of the classical arguments for substance. ..Any conceptual scheme which genuinely represents a world cannot contain infinite backward chains of meaning. | |
| From: Michael Potter (Set Theory and Its Philosophy [2004], 03.3) | |
| A reaction: Thus the iterative conception of set may imply a notion of substance, and Barwise's radical attempt to ditch the Axiom of Foundation (Idea 13039) was a radical attempt to get rid of 'substances'. Potter cites Wittgenstein as a fan of substances here. |