28 ideas
| 8623 | Proof reveals the interdependence of truths, as well as showing their certainty [Euclid, by Frege] |
| 11074 | 'It is true that this follows' means simply: this follows [Wittgenstein] |
| 13907 | If you pick an arbitrary triangle, things proved of it are true of all triangles [Euclid, by Lemmon] |
| 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] |
| 11073 | Two and one making three has the necessity of logical inference [Wittgenstein] |
| 21202 | The strong force has a considerably greater range than the weak force [Martin,BR] |
| 21211 | If an expected reaction does not occur, that implies a conservation law [Martin,BR] |
| 21209 | Electron emit and reabsorb photons, which create and reabsorb virtual electrons and positrons [Martin,BR] |
| 21212 | The Higgs field, unlike others, has a nozero value in a state without particles [Martin,BR] |
| 21201 | A 'field' is just a region to which points can be assigned in space and time [Martin,BR] |
| 21205 | Many physicists believe particles have further structure, if only we could see it [Martin,BR] |
| 21203 | Uncertainty allows very brief violations of energy conservation - even shorter with higher energies [Martin,BR] |
| 21207 | The Exclusion Principle says no two fermions occupy the same state, with the same numbers [Martin,BR] |
| 21204 | The standard model combines theories of strong interaction, and electromagnetic and weak interaction [Martin,BR] |
| 21208 | Eletrons don't literally 'spin', because they are point-like [Martin,BR] |
| 21210 | Virtual particles surround any charged particle [Martin,BR] |
| 21206 | The properties of a particle are determined by its quantum numbers and its mass [Martin,BR] |
| 21213 | String theory only has one free parameter (tension) - unlike the standard model with 19 [Martin,BR] |
| 21200 | An 'element' is what cannot be decomposed by chemistry [Martin,BR] |