4 ideas
15990 | Every individual thing which exists has an essence, which is its internal constitution [Locke] |
13166 | Essences are no use in mathematics, if all mathematical truths are necessary [Mancosu] |
15994 | If it is knowledge, it is certain; if it isn't certain, it isn't knowledge [Locke] |
9425 | Lewis later proposed the axioms at the intersection of the best theories (which may be few) [Mumford on Lewis] |