47 ideas
| 17925 | Showing a disproof is impossible is not a proof, so don't eliminate double negation [Colyvan] |
| 17926 | Rejecting double negation elimination undermines reductio proofs [Colyvan] |
| 15845 | It seems absurd that seeing a person's limbs, the one is many, and yet the many are one [Plato] |
| 17924 | Excluded middle says P or not-P; bivalence says P is either true or false [Colyvan] |
| 17929 | Löwenheim proved his result for a first-order sentence, and Skolem generalised it [Colyvan] |
| 17930 | Axioms are 'categorical' if all of their models are isomorphic [Colyvan] |
| 9867 | It is absurd to define a circle, but not be able to recognise a real one [Plato] |
| 17928 | Ordinal numbers represent order relations [Colyvan] |
| 9865 | Daily arithmetic counts unequal things, but pure arithmetic equalises them [Plato] |
| 17923 | Intuitionists only accept a few safe infinities [Colyvan] |
| 17941 | Infinitesimals were sometimes zero, and sometimes close to zero [Colyvan] |
| 17922 | Reducing real numbers to rationals suggested arithmetic as the foundation of maths [Colyvan] |
| 13007 | Archimedes defined a straight line as the shortest distance between two points [Archimedes, by Leibniz] |
| 17936 | Transfinite induction moves from all cases, up to the limit ordinal [Colyvan] |
| 17940 | Most mathematical proofs are using set theory, but without saying so [Colyvan] |
| 17931 | Structuralism say only 'up to isomorphism' matters because that is all there is to it [Colyvan] |
| 17932 | If 'in re' structures relies on the world, does the world contain rich enough structures? [Colyvan] |
| 14503 | If a mixture does not contain measure and proportion, it is corrupted and destroyed [Plato] |
| 15857 | Any mixture which lacks measure and proportion doesn't even count as a mixture at all [Plato] |
| 4447 | If the good is one, is it unchanged when it is in particulars, and is it then separated from itself? [Plato] |
| 15856 | A thing can become one or many, depending on how we talk about it [Plato] |
| 374 | If one object is divided into its parts, someone can then say that one are many and many is one [Plato] |
| 389 | How can you be certain about aspects of the world if they aren't constant? [Plato] |
| 17943 | Probability supports Bayesianism better as degrees of belief than as ratios of frequencies [Colyvan] |
| 17939 | Mathematics can reveal structural similarities in diverse systems [Colyvan] |
| 17938 | Mathematics can show why some surprising events have to occur [Colyvan] |
| 17934 | Proof by cases (by 'exhaustion') is said to be unexplanatory [Colyvan] |
| 17933 | Reductio proofs do not seem to be very explanatory [Colyvan] |
| 17935 | If inductive proofs hold because of the structure of natural numbers, they may explain theorems [Colyvan] |
| 17942 | Can a proof that no one understands (of the four-colour theorem) really be a proof? [Colyvan] |
| 17937 | Mathematical generalisation is by extending a system, or by abstracting away from it [Colyvan] |
| 390 | If goodness involves moderation and proportion, then it seems to be found in beauty [Plato] |
| 391 | The good involves beauty, proportion and truth [Plato] |
| 392 | Neither intellect nor pleasure are the good, because they are not perfect and self-sufficient [Plato] |
| 393 | Good first, then beauty, then reason, then knowledge, then pleasure [Plato, by PG] |
| 385 | Some of the pleasures and pains we feel are false [Plato] |
| 387 | A small pure pleasure is much finer than a large one contaminated with pain [Plato] |
| 373 | Pleasure is certainly very pleasant, but it doesn't follow that all pleasures are good [Plato] |
| 371 | Reason, memory, truth and wisdom are far better than pleasure, for those who can attain them [Plato] |
| 382 | It is unlikely that the gods feel either pleasure or pain [Plato] |
| 376 | Would you prefer a life of pleasure without reason, or one of reason without pleasure? [Plato] |
| 379 | The good must be sufficient and perfect, and neither intellect nor pleasure are that [Plato] |
| 381 | We feel pleasure when we approach our natural state of harmony [Plato] |
| 386 | Intense pleasure and pain are not felt in a good body, but in a worthless one [Plato] |
| 388 | Hedonists must say that someone in pain is bad, even if they are virtuous [Plato] |
| 377 | If you lived a life of maximum pleasure, would you still be lacking anything? [Plato] |
| 378 | A life of pure pleasure with no intellect is the life of a jellyfish [Plato] |