92 ideas
9786 | Philosophers working like teams of scientists is absurd, yet isolation is hard [Cartwright,R] |
9784 | A false proposition isn't truer because it is part of a coherent system [Cartwright,R] |
13941 | Are the truth-bearers sentences, utterances, ideas, beliefs, judgements, propositions or statements? [Cartwright,R] |
13942 | Logicians take sentences to be truth-bearers for rigour, rather than for philosophical reasons [Cartwright,R] |
15901 | Trying to represent curves, we study arbitrary functions, leading to the ordinals, which produces set theory [Cantor, by Lavine] |
15946 | Cantor developed sets from a progression into infinity by addition, multiplication and exponentiation [Cantor, by Lavine] |
9616 | A set is a collection into a whole of distinct objects of our intuition or thought [Cantor] |
13444 | Cantor's Theorem: for any set x, its power set P(x) has more members than x [Cantor, by Hart,WD] |
18098 | Cantor proved that all sets have more subsets than they have members [Cantor, by Bostock] |
15505 | If a set is 'a many thought of as one', beginners should protest against singleton sets [Cantor, by Lewis] |
10865 | The continuum is the powerset of the integers, which moves up a level [Cantor, by Clegg] |
10701 | Cantor showed that supposed contradictions in infinity were just a lack of clarity [Cantor, by Potter] |
17831 | Cantor gives informal versions of ZF axioms as ways of getting from one set to another [Cantor, by Lake] |
13016 | The Axiom of Union dates from 1899, and seems fairly obvious [Cantor, by Maddy] |
14199 | Cantor's sets were just collections, but Dedekind's were containers [Cantor, by Oliver/Smiley] |
10082 | There are infinite sets that are not enumerable [Cantor, by Smith,P] |
13483 | Cantor's Paradox: the power set of the universe must be bigger than the universe, yet a subset of it [Cantor, by Hart,WD] |
8710 | The powerset of all the cardinal numbers is required to be greater than itself [Cantor, by Friend] |
15910 | Cantor named the third realm between the finite and the Absolute the 'transfinite' [Cantor, by Lavine] |
15905 | Cantor proved the points on a plane are in one-to-one correspondence to the points on a line [Cantor, by Lavine] |
9983 | Cantor took the ordinal numbers to be primary [Cantor, by Tait] |
17798 | Cantor presented the totality of natural numbers as finite, not infinite [Cantor, by Mayberry] |
9971 | Cantor introduced the distinction between cardinals and ordinals [Cantor, by Tait] |
9892 | Cantor showed that ordinals are more basic than cardinals [Cantor, by Dummett] |
15911 | Ordinals are generated by endless succession, followed by a limit ordinal [Cantor, by Lavine] |
14136 | A cardinal is an abstraction, from the nature of a set's elements, and from their order [Cantor] |
15906 | Cantor tried to prove points on a line matched naturals or reals - but nothing in between [Cantor, by Lavine] |
11015 | Cantor's diagonal argument proved you can't list all decimal numbers between 0 and 1 [Cantor, by Read] |
15903 | A real is associated with an infinite set of infinite Cauchy sequences of rationals [Cantor, by Lavine] |
18251 | Irrational numbers are the limits of Cauchy sequences of rational numbers [Cantor, by Lavine] |
15902 | Irrationals and the Dedekind Cut implied infinite classes, but they seemed to have logical difficulties [Cantor, by Lavine] |
15908 | It was Cantor's diagonal argument which revealed infinities greater than that of the real numbers [Cantor, by Lavine] |
13464 | Cantor proposes that there won't be a potential infinity if there is no actual infinity [Cantor, by Hart,WD] |
10112 | The naturals won't map onto the reals, so there are different sizes of infinity [Cantor, by George/Velleman] |
15896 | Cantor needed Power Set for the reals, but then couldn't count the new collections [Cantor, by Lavine] |
17889 | CH: An infinite set of reals corresponds 1-1 either to the naturals or to the reals [Cantor, by Koellner] |
8733 | The Continuum Hypothesis says there are no sets between the natural numbers and reals [Cantor, by Shapiro] |
13447 | Cantor: there is no size between naturals and reals, or between a set and its power set [Cantor, by Hart,WD] |
10883 | Cantor's Continuum Hypothesis says there is a gap between the natural and the real numbers [Cantor, by Horsten] |
13528 | Continuum Hypothesis: there are no sets between N and P(N) [Cantor, by Wolf,RS] |
9555 | Continuum Hypothesis: no cardinal greater than aleph-null but less than cardinality of the continuum [Cantor, by Chihara] |
15893 | Cantor's theory concerns collections which can be counted, using the ordinals [Cantor, by Lavine] |
18174 | Cantor extended ordinals into the transfinite, and they can thus measure infinite cardinalities [Cantor, by Maddy] |
18173 | Cardinality strictly concerns one-one correspondence, to test infinite sameness of size [Cantor, by Maddy] |
9992 | The 'extension of a concept' in general may be quantitatively completely indeterminate [Cantor] |
10232 | Property extensions outstrip objects, so shortage of objects caused the Caesar problem [Cantor, by Shapiro] |
18176 | Pure mathematics is pure set theory [Cantor] |
8631 | Cantor says that maths originates only by abstraction from objects [Cantor, by Frege] |
16661 | There are two sorts of category - referring to things, and to circumstances of things [Boethius] |
9783 | While no two classes coincide in membership, there are distinct but coextensive attributes [Cartwright,R] |
15035 | If universals are not separate, we can isolate them by abstraction [Boethius, by Panaccio] |
14665 | We can call the quality of Plato 'Platonity', and say it is a quality which only he possesses [Boethius] |
14961 | Clearly a pipe can survive being taken apart [Cartwright,R] |
14962 | Bodies don't becomes scattered by losing small or minor parts [Cartwright,R] |
13952 | Essentialism says some of a thing's properties are necessary, and could not be absent [Cartwright,R] |
13954 | The difficulty in essentialism is deciding the grounds for rating an attribute as essential [Cartwright,R] |
13955 | Essentialism is said to be unintelligible, because relative, if necessary truths are all analytic [Cartwright,R] |
13953 | An act of ostension doesn't seem to need a 'sort' of thing, even of a very broad kind [Cartwright,R] |
13945 | A token isn't a unique occurrence, as the case of a word or a number shows [Cartwright,R] |
23308 | Reasoning relates to understanding as time does to eternity [Boethius, by Sorabji] |
5771 | Knowledge of present events doesn't make them necessary, so future events are no different [Boethius] |
5767 | Rational natures require free will, in order to have power of judgement [Boethius] |
5768 | God's universal foreknowledge seems opposed to free will [Boethius] |
5769 | Does foreknowledge cause necessity, or necessity cause foreknowledge? [Boethius] |
8715 | Infinities expand the bounds of the conceivable; we explore concepts to explore conceivability [Cantor, by Friend] |
13454 | Cantor says (vaguely) that we abstract numbers from equal sized sets [Hart,WD on Cantor] |
9145 | We form the image of a cardinal number by a double abstraction, from the elements and from their order [Cantor] |
13950 | People don't assert the meaning of the words they utter [Cartwright,R] |
13948 | For any statement, there is no one meaning which any sentence asserting it must have [Cartwright,R] |
13944 | We can pull apart assertion from utterance, and the action, the event and the subject-matter for each [Cartwright,R] |
13947 | 'It's raining' makes a different assertion on different occasions, but its meaning remains the same [Cartwright,R] |
13943 | We can attribute 'true' and 'false' to whatever it was that was said [Cartwright,R] |
13946 | To assert that p, it is neither necessary nor sufficient to utter some particular words [Cartwright,R] |
13951 | Assertions, unlike sentence meanings, can be accurate, probable, exaggerated, false.... [Cartwright,R] |
5762 | The wicked want goodness, so they would not be wicked if they obtained it [Boethius] |
5770 | Rewards and punishments are not deserved if they don't arise from free movement of the mind [Boethius] |
5764 | When people fall into wickedness they lose their human nature [Boethius] |
5756 | Happiness is a good which once obtained leaves nothing more to be desired [Boethius] |
5763 | The bad seek the good through desire, but the good through virtue, which is more natural [Boethius] |
5759 | Varied aims cannot be good because they differ, but only become good when they unify [Boethius] |
5754 | You can't control someone's free mind, only their body and possessions [Boethius] |
10863 | Cantor proved that three dimensions have the same number of points as one dimension [Cantor, by Clegg] |
13465 | Only God is absolutely infinite [Cantor, by Hart,WD] |
16692 | Divine eternity is the all-at-once and complete possession of unending life [Boethius] |
5752 | Where does evil come from if there is a god; where does good come from if there isn't? [Boethius] |
5757 | God is the supreme good, so no source of goodness could take precedence over God [Boethius] |
5758 | God is the good [Boethius] |
5760 | The power through which creation remains in existence and motion I call 'God' [Boethius] |
5753 | The regular events of this life could never be due to chance [Boethius] |
5765 | The reward of the good is to become gods [Boethius] |
5761 | God can do anything, but he cannot do evil, so evil must be nothing [Boethius] |
5766 | If you could see the plan of Providence, you would not think there was evil anywhere [Boethius] |