84 ideas
15901 | Trying to represent curves, we study arbitrary functions, leading to the ordinals, which produces set theory [Cantor, by Lavine] |
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] |
10701 | Cantor showed that supposed contradictions in infinity were just a lack of clarity [Cantor, by Potter] |
10865 | The continuum is the powerset of the integers, which moves up a level [Cantor, by Clegg] |
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] |
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] |
8733 | The Continuum Hypothesis says there are no sets between the natural numbers and reals [Cantor, by Shapiro] |
17889 | CH: An infinite set of reals corresponds 1-1 either to the naturals or to the reals [Cantor, by Koellner] |
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] |
18174 | Cantor extended ordinals into the transfinite, and they can thus measure infinite cardinalities [Cantor, by Maddy] |
15893 | Cantor's theory concerns collections which can be counted, using the ordinals [Cantor, by Lavine] |
18173 | Cardinality strictly concerns one-one correspondence, to test infinite sameness of size [Cantor, by Maddy] |
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] |
13768 | Validity can preserve certainty in mathematics, but conditionals about contingents are another matter [Edgington] |
13770 | There are many different conditional mental states, and different conditional speech acts [Edgington] |
13764 | Are conditionals truth-functional - do the truth values of A and B determine the truth value of 'If A, B'? [Edgington] |
13765 | 'If A,B' must entail ¬(A & ¬B); otherwise we could have A true, B false, and If A,B true, invalidating modus ponens [Edgington] |
23101 | Intuitions don't prove things; they just receptivity to interpretations [Kekes] |
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] |
23086 | Liberals say we are only responsible for fully autonomous actions [Kekes] |
23100 | Collective responsibility conflicts with responsibility's requirement of authonomy [Kekes] |
23093 | Moral and causal responsibility are not clearly distinct [Kekes] |
23096 | Morality should aim to prevent all evil actions, not just autonomous ones [Kekes] |
23087 | Much human evil is not autonomous, so moral responsibility need not be autonomous [Kekes] |
23098 | Effects show the existence of moral responsibility, and mental states show the degree [Kekes] |
23089 | Evil people may not be autonomously aware, if they misjudge the situation [Kekes] |
23094 | Ought implies can means moral responsibility needs autonomy [Kekes] |
23095 | Why should moral responsibility depend on autonomy, rather than social role or experience? [Kekes] |
23090 | Liberals assume people are naturally free, equal, rational, and morally good [Kekes] |
23117 | Love should be partial, and discriminate in favour of its object [Kekes] |
23119 | Sentimental love distorts its object [Kekes] |
23088 | Evil is not deviation from the good, any more than good is a deviation from evil [Kekes] |
23097 | What matters for morality is the effects of action, not the psychological causes [Kekes] |
23099 | It is said that if an agent is not autonomous then their evil actions don't reflect on their character [Kekes] |
23118 | Awareness of others' suffering doesn't create an obligation to help [Kekes] |
23109 | The veil of ignorance is only needed because people have bad motivations [Kekes] |
23114 | The chief function of the state is to arbitrate between contending visions of the good life [Kekes] |
23116 | Citizenship is easier than parenthood [Kekes] |
23103 | Power is meant to be confined to representatives, and subsequent delegation [Kekes] |
23107 | Prosperity is a higher social virtue than justice [Kekes] |
23081 | Liberal basics are pluralism, freedom, rights, equality, and distributive justice - for autonomy [Kekes] |
23085 | The key liberal values are explained by the one core value, which is autonomy [Kekes] |
23092 | Agents have little control over the capacities needed for liberal autonomy [Kekes] |
23102 | Liberals are egalitarians, but in varying degrees [Kekes] |
23084 | Are egalitarians too coercive, or not egalitarian enough, or lax over morality? [Kekes] |
23079 | Liberal justice ignores desert, which is the essence of justice [Kekes] |
23091 | Why do liberals not see a much wider range of values as basic? [Kekes] |
23112 | Liberals ignore contingency, and think people are good and equal, and institutions cause evil [Kekes] |
23082 | Liberal distribution cares more about recipients than donors [Kekes] |
23106 | To rectify the undeserved equality, we should give men longer and women shorter lives [Kekes] |
23121 | It is just a fact that some people are morally better than others [Kekes] |
23105 | It is not deplorable that billionaires have more than millionaires [Kekes] |
23120 | The problem is basic insufficiency of resources, not their inequality [Kekes] |
23108 | Justice combines consistency and desert; treat likes alike, judging likeness by desert [Kekes] |
23083 | Liberal welfare focuses on need rather than desert [Kekes] |
23113 | Sexual morality doesn't require monogamy, but it needs a group of sensible regulations [Kekes] |
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] |