4 ideas
10053 | Geometrical axioms imply the propositions, but the former may not be true [Russell] |
Full Idea: We must only assert of various geometries that the axioms imply the propositions, not that the axioms are true and therefore that the propositions are true. | |
From: Bertrand Russell (Foundations of Geometry [1897], Intro vii), quoted by Alan Musgrave - Logicism Revisited §4 | |
A reaction: Clearly the truth of the axioms can remain a separate issue from whether they actually imply the theorems. The truth of the axioms might be as much a metaphysical as an empirical question. Musgrave sees this as the birth of if-thenism. |
10052 | Geometry is united by the intuitive axioms of projective geometry [Russell, by Musgrave] |
Full Idea: Russell sought what was common to Euclidean and non-Euclidean systems, found it in the axioms of projective geometry, and took a Kantian view of them. | |
From: report of Bertrand Russell (Foundations of Geometry [1897]) by Alan Musgrave - Logicism Revisited §4 | |
A reaction: Russell's work just preceded Hilbert's famous book. Tarski later produced some logical axioms for geometry. |
16695 | Successive entities are in flux, flowing in existence, with different parts at different times [Oresme] |
Full Idea: For any time, some of a successive entity exists in one of its parts, and a totally different such exists in another part. …It is in continuous flux and transition, ..and flows in existence if it does not have the same existence over a whole time. | |
From: Nicole Oresme (On 'Physics' [1346], III.6, dist.1), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 18.1 | |
A reaction: Pasnau says the successive entity is the whole made up of these changing parts, so it sounds very like the temporal stages view of Sider and Hawley. |
468 | Musical performance can reveal a range of virtues [Damon of Ath.] |
Full Idea: In singing and playing the lyre, a boy will be likely to reveal not only courage and moderation, but also justice. | |
From: Damon (fragments/reports [c.460 BCE], B4), quoted by (who?) - where? |