24 ideas
9283 | Our ancient beliefs can never be overthrown by subtle arguments [Euripides] |
8623 | Proof reveals the interdependence of truths, as well as showing their certainty [Euclid, by Frege] |
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] |
17453 | The meaning of a number isn't just the numerals leading up to it [Heck] |
9603 | An assumption that there is a largest prime leads to a contradiction [Euclid, by Brown,JR] |
17457 | A basic grasp of cardinal numbers needs an understanding of equinumerosity [Heck] |
9894 | A unit is that according to which each existing thing is said to be one [Euclid] |
17448 | In counting, numerals are used, not mentioned (as objects that have to correlated) [Heck] |
17455 | Is counting basically mindless, and independent of the cardinality involved? [Heck] |
17456 | Counting is the assignment of successively larger cardinal numbers to collections [Heck] |
17450 | Understanding 'just as many' needn't involve grasping one-one correspondence [Heck] |
17451 | We can know 'just as many' without the concepts of equinumerosity or numbers [Heck] |
8738 | Postulate 2 says a line can be extended continuously [Euclid, by Shapiro] |
10302 | Euclid says we can 'join' two points, but Hilbert says the straight line 'exists' [Euclid, by Bernays] |
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] |
14157 | Modern geometries only accept various parts of the Euclid propositions [Russell on Euclid] |
17459 | Frege's Theorem explains why the numbers satisfy the Peano axioms [Heck] |
1600 | Euclid's common notions or axioms are what we must have if we are to learn anything at all [Euclid, by Roochnik] |
17454 | Children can use numbers, without a concept of them as countable objects [Heck] |
17449 | We can understand cardinality without the idea of one-one correspondence [Heck] |
17458 | Equinumerosity is not the same concept as one-one correspondence [Heck] |