32 ideas
17926 | Rejecting double negation elimination undermines reductio proofs [Colyvan] |
17925 | Showing a disproof is impossible is not a proof, so don't eliminate double negation [Colyvan] |
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] |
17928 | Ordinal numbers represent order relations [Colyvan] |
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] |
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] |
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] |
468 | Musical performance can reveal a range of virtues [Damon of Ath.] |
23865 | Morality would improve if people could pursue private interests [Weil] |
23866 | In oppressive societies the scope of actual control is extended by a religion of power [Weil] |
23871 | No central authority can initiate decentralisation [Weil] |
23867 | After a bloody revolution the group which already had the power comes to the fore [Weil] |
23870 | Decentralisation is only possible by co-operation between strong and weak - which is absurd [Weil] |
23863 | Only individual people of good will can achieve social progress [Weil] |
23869 | In the least evil societies people can think, control community life, and be autonomous [Weil] |
23861 | Marx showed that capitalist oppression, because of competition, is unstoppable [Weil] |
23868 | The pleasure of completing tasks motivates just as well as the whip of slavery [Weil] |
23864 | Inequality could easily be mitigated, if it were not for the struggle for power [Weil] |