89 ideas
22733 | Epicurus accepted God in his popular works, but not in his writings on nature [Epicurus, by Sext.Empiricus] |
13291 | Slavery to philosophy brings true freedom [Epicurus] |
22758 | Philosophy aims at a happy life, through argument and discussion [Epicurus] |
14523 | We should come to philosophy free from any taint of culture [Epicurus] |
22240 | The aim of medicine is removal of sickness, and philosophy similarly removes our affections [Epicurus] |
1484 | We should say nothing of the whole if our contact is with the parts [Epicurus, by Plutarch] |
2670 | Epicurus despises and laughs at the whole of dialectic [Epicurus, by Cicero] |
9955 | Contextual definitions replace a complete sentence containing the expression [George/Velleman] |
10031 | Impredicative definitions quantify over the thing being defined [George/Velleman] |
10098 | The 'power set' of A is all the subsets of A [George/Velleman] |
10099 | The 'ordered pair' <a, b>, for two sets a and b, is the set {{a, b},{a}} [George/Velleman] |
10101 | Cartesian Product A x B: the set of all ordered pairs in which a∈A and b∈B [George/Velleman] |
10103 | Grouping by property is common in mathematics, usually using equivalence [George/Velleman] |
10104 | 'Equivalence' is a reflexive, symmetric and transitive relation; 'same first letter' partitions English words [George/Velleman] |
10096 | Even the elements of sets in ZFC are sets, resting on the pure empty set [George/Velleman] |
10097 | Axiom of Extensionality: for all sets x and y, if x and y have the same elements then x = y [George/Velleman] |
10100 | Axiom of Pairing: for all sets x and y, there is a set z containing just x and y [George/Velleman] |
17900 | The Axiom of Reducibility made impredicative definitions possible [George/Velleman] |
10109 | ZFC can prove that there is no set corresponding to the concept 'set' [George/Velleman] |
10108 | As a reduction of arithmetic, set theory is not fully general, and so not logical [George/Velleman] |
21668 | Epicurus rejected excluded middle, because accepting it for events is fatalistic [Epicurus, by Cicero] |
10111 | Asserting Excluded Middle is a hallmark of realism about the natural world [George/Velleman] |
21676 | Epicureans say disjunctions can be true whiile the disjuncts are not true [Epicurus, by Cicero] |
10129 | A 'model' is a meaning-assignment which makes all the axioms true [George/Velleman] |
10105 | Differences between isomorphic structures seem unimportant [George/Velleman] |
10119 | Consistency is a purely syntactic property, unlike the semantic property of soundness [George/Velleman] |
10126 | A 'consistent' theory cannot contain both a sentence and its negation [George/Velleman] |
10120 | Soundness is a semantic property, unlike the purely syntactic property of consistency [George/Velleman] |
10127 | A 'complete' theory contains either any sentence or its negation [George/Velleman] |
10106 | Rational numbers give answers to division problems with integers [George/Velleman] |
10102 | The integers are answers to subtraction problems involving natural numbers [George/Velleman] |
10107 | Real numbers provide answers to square root problems [George/Velleman] |
9946 | Logicists say mathematics is applicable because it is totally general [George/Velleman] |
10125 | The classical mathematician believes the real numbers form an actual set [George/Velleman] |
17899 | Second-order induction is stronger as it covers all concepts, not just first-order definable ones [George/Velleman] |
10128 | The Incompleteness proofs use arithmetic to talk about formal arithmetic [George/Velleman] |
17902 | A successor is the union of a set with its singleton [George/Velleman] |
10133 | Frege's Theorem shows the Peano Postulates can be derived from Hume's Principle [George/Velleman] |
10130 | Set theory can prove the Peano Postulates [George/Velleman] |
10089 | Talk of 'abstract entities' is more a label for the problem than a solution to it [George/Velleman] |
10131 | If mathematics is not about particulars, observing particulars must be irrelevant [George/Velleman] |
17901 | Type theory prohibits (oddly) a set containing an individual and a set of individuals [George/Velleman] |
10092 | In the unramified theory of types, the types are objects, then sets of objects, sets of sets etc. [George/Velleman] |
10094 | The theory of types seems to rule out harmless sets as well as paradoxical ones. [George/Velleman] |
10095 | Type theory has only finitely many items at each level, which is a problem for mathematics [George/Velleman] |
10134 | Much infinite mathematics can still be justified finitely [George/Velleman] |
10114 | Bounded quantification is originally finitary, as conjunctions and disjunctions [George/Velleman] |
10123 | The intuitionists are the idealists of mathematics [George/Velleman] |
10124 | Gödel's First Theorem suggests there are truths which are independent of proof [George/Velleman] |
1823 | We can't seek for things if we have no idea of them [Epicurus, by Diog. Laertius] |
1824 | To name something, you must already have an idea of what it is [Epicurus, by Diog. Laertius] |
5949 | Epicurus says colours are relative to the eye, not intrinsic to bodies [Epicurus, by Plutarch] |
1821 | Sensations cannot be judged, because similar sensations have equal value, and different ones have nothing in common [Epicurus, by Diog. Laertius] |
1820 | The criteria of truth are senses, preconceptions and passions [Epicurus, by Diog. Laertius] |
1822 | Reason can't judge senses, as it is based on them [Epicurus, by Diog. Laertius] |
4549 | Epicurus denied knowledge in order to retain morality or hedonism as the highest values [Nietzsche on Epicurus] |
2668 | Epicurus says if one of a man's senses ever lies, none of his senses should ever be believed [Epicurus, by Cicero] |
1487 | When entering a dark room it is colourless, but colour gradually appears [Epicurus] |
1483 | Bath water is too hot for some, too cold for others [Epicurus, by Plutarch] |
1482 | If two people disagree over taste, who is right? [Epicurus, by Plutarch] |
14526 | The rational soul is in the chest, and the non-rational soul is spread through the body [Epicurus] |
6035 | Soul is made of four stuffs, giving warmth, rest, motion and perception [Epicurus, by Aetius] |
6018 | Epicurus was the first to see the free will problem, and he was a libertarian [Epicurus, by Long/Sedley] |
20922 | Epicurus showed that the swerve can give free motion in the atoms [Epicurus, by Diogenes of Oen.] |
14516 | There is no necessity to live with necessity [Epicurus] |
1909 | How can pleasure or judgement occur in a heap of atoms? [Sext.Empiricus on Epicurus] |
10110 | Corresponding to every concept there is a class (some of them sets) [George/Velleman] |
7814 | It was Epicurus who made the question of the will's freedom central to ethics [Epicurus, by Grayling] |
3562 | Fine things are worthless if they give no pleasure [Epicurus] |
1840 | Pleasure is the chief good because it is the most natural, especially for animals [Epicurus, by Diog. Laertius] |
3557 | The end for Epicurus is static pleasure [Epicurus, by Annas] |
1839 | Pains of the soul are worse than pains of the body, because it feels the past and future [Epicurus, by Diog. Laertius] |
1842 | Pleasures only differ in their duration and the part of the body affected [Epicurus] |
1845 | Justice has no independent existence, but arises entirely from keeping contracts [Epicurus] |
1841 | We choose virtue because of pleasure, not for its own sake [Epicurus, by Diog. Laertius] |
1829 | A wise man would be happy even under torture [Epicurus, by Diog. Laertius] |
1843 | Friendship is by far the most important ingredient of a complete and happy life [Epicurus] |
1831 | Wise men should partake of life even if they go blind [Epicurus, by Diog. Laertius] |
12044 | Only Epicurus denied purpose in nature, for the whole world, or for its parts [Epicurus, by Annas] |
1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
20907 | Democritus says atoms have size and shape, and Epicurus added weight [Epicurus, by Ps-Plutarch] |
21669 | Atoms don't swerve by being struck, because they move in parallel, so the swerve is uncaused [Cicero on Epicurus] |
21680 | What causes atomic swerves? Do they draw lots? What decides the size or number of swerves? [Cicero on Epicurus] |
14525 | Stoics say time is incorporeal and self-sufficient; Epicurus says it is a property of properties of things [Epicurus] |
5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |
2637 | For Epicureans gods are made of atoms, and are not eternal [Epicurus, by Cicero] |
2633 | Epicurus saw that gods must exist, because nature has imprinted them on human minds [Epicurus, by Cicero] |
2639 | Some say Epicurus only pretended to believe in the gods, so as not to offend Athenians [Epicurus, by Cicero] |
14527 | If god answered prayers we would be destroyed, because we pray for others to suffer [Epicurus] |