35 ideas
| 12124 | Metaphysics is the best knowledge, because it is the simplest [Bacon] |
| 12123 | Natural history supports physical knowledge, which supports metaphysical knowledge [Bacon] |
| 12119 | Physics studies transitory matter; metaphysics what is abstracted and necessary [Bacon] |
| 12120 | Physics is of material and efficient causes, metaphysics of formal and final causes [Bacon] |
| 8623 | Proof reveals the interdependence of truths, as well as showing their certainty [Euclid, by Frege] |
| 21544 | It seems that when a proposition is false, something must fail to subsist [Russell] |
| 13907 | If you pick an arbitrary triangle, things proved of it are true of all triangles [Euclid, by Lemmon] |
| 21539 | Excluded middle can be stated psychologically, as denial of p implies assertion of not-p [Russell] |
| 6297 | Euclid's geometry is synthetic, but Descartes produced an analytic version of it [Euclid, by Resnik] |
| 9603 | An assumption that there is a largest prime leads to a contradiction [Euclid, by Brown,JR] |
| 9894 | A unit is that according to which each existing thing is said to be one [Euclid] |
| 8738 | Postulate 2 says a line can be extended continuously [Euclid, by Shapiro] |
| 22278 | Euclid relied on obvious properties in diagrams, as well as on his axioms [Potter on Euclid] |
| 8673 | Euclid's parallel postulate defines unique non-intersecting parallel lines [Euclid, by Friend] |
| 10250 | Euclid needs a principle of continuity, saying some lines must intersect [Shapiro on Euclid] |
| 10302 | Euclid says we can 'join' two points, but Hilbert says the straight line 'exists' [Euclid, by Bernays] |
| 14157 | Modern geometries only accept various parts of the Euclid propositions [Russell on Euclid] |
| 1600 | Euclid's common notions or axioms are what we must have if we are to learn anything at all [Euclid, by Roochnik] |
| 21538 | If two people perceive the same object, the object of perception can't be in the mind [Russell] |
| 21534 | The only thing we can say about relations is that they relate [Russell] |
| 21540 | Relational propositions seem to be 'about' their terms, rather than about the relation [Russell] |
| 21536 | When I perceive a melody, I do not perceive the notes as existing [Russell] |
| 21535 | Objects only exist if they 'occupy' space and time [Russell] |
| 21533 | Contingency arises from tensed verbs changing the propositions to which they refer [Russell] |
| 21537 | I assume we perceive the actual objects, and not their 'presentations' [Russell] |
| 12121 | We don't assume there is no land, because we can only see sea [Bacon] |
| 21532 | Full empiricism is not tenable, but empirical investigation is always essential [Russell] |
| 12117 | Science moves up and down between inventions of causes, and experiments [Bacon] |
| 12127 | Many different theories will fit the observed facts [Bacon] |
| 12126 | People love (unfortunately) extreme generality, rather than particular knowledge [Bacon] |
| 21542 | Do incorrect judgements have non-existent, or mental, or external objects? [Russell] |
| 21541 | The complexity of the content correlates with the complexity of the object [Russell] |
| 21543 | If p is false, then believing not-p is knowing a truth, so negative propositions must exist [Russell] |
| 12125 | Teleological accounts are fine in metaphysics, but they stop us from searching for the causes [Bacon] |
| 12118 | Essences are part of first philosophy, but as part of nature, not part of logic [Bacon] |