101 ideas
5486 | Essentialism says metaphysics can't be done by analysing unreliable language [Ellis] |
3123 | Science is in the business of carving nature at the joints [Segal] |
3125 | Psychology studies the way rationality links desires and beliefs to causality [Segal] |
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] |
5468 | Properties are 'dispositional', or 'categorical' (the latter as 'block' or 'intrinsic' structures) [Ellis, by PG] |
5469 | The passive view of nature says categorical properties are basic, but others say dispositions [Ellis] |
5456 | Redness is not a property as it is not mind-independent [Ellis] |
5481 | Properties have powers; they aren't just ways for logicians to classify objects [Ellis] |
5458 | Nearly all fundamental properties of physics are dispositional [Ellis] |
5443 | Kripke and others have made essentialism once again respectable [Ellis] |
5444 | 'Individual essences' fix a particular individual, and 'kind essences' fix the kind it belongs to [Ellis] |
5462 | Essential properties are usually quantitatively determinate [Ellis] |
5448 | 'Real essence' makes it what it is; 'nominal essence' makes us categorise it a certain way [Ellis] |
5477 | One thing can look like something else, without being the something else [Ellis] |
3105 | Is 'Hesperus = Phosphorus' metaphysically necessary, but not logically or epistemologically necessary? [Segal] |
5479 | Scientific essentialists say science should define the limits of the possible [Ellis] |
5483 | Essentialists deny possible worlds, and say possibilities are what is compatible with the actual world [Ellis] |
5447 | Metaphysical necessities are true in virtue of the essences of things [Ellis] |
5476 | Essentialists say natural laws are in a new category: necessary a posteriori [Ellis] |
5478 | Imagination tests what is possible for all we know, not true possibility [Ellis] |
3106 | If claims of metaphysical necessity are based on conceivability, we should be cautious [Segal] |
5482 | Possible worlds realism is only needed to give truth conditions for modals and conditionals [Ellis] |
5453 | Essentialists mostly accept the primary/secondary qualities distinction [Ellis] |
5466 | Primary qualities are number, figure, size, texture, motion, configuration, impenetrability and (?) mass [Ellis] |
5485 | Emeralds are naturally green, and only an external force could turn them blue [Ellis] |
5484 | Essentialists don't infer from some to all, but from essences to necessary behaviour [Ellis] |
3113 | The success and virtue of an explanation do not guarantee its truth [Segal] |
3112 | Folk psychology is ridiculously dualist in its assumptions [Segal] |
3108 | If 'water' has narrow content, it refers to both H2O and XYZ [Segal] |
3110 | Humans are made of H2O, so 'twins' aren't actually feasible [Segal] |
3124 | Externalists can't assume old words refer to modern natural kinds [Segal] |
3117 | Concepts can survive a big change in extension [Segal] |
3104 | Must we relate to some diamonds to understand them? [Segal] |
3103 | Maybe content involves relations to a language community [Segal] |
3111 | Externalism can't explain concepts that have no reference [Segal] |
3109 | If content is external, so are beliefs and desires [Segal] |
3116 | Maybe experts fix content, not ordinary users [Segal] |
3121 | If content is narrow, my perfect twin shares my concepts [Segal] |
3119 | Even 'mass' cannot be defined in causal terms [Segal] |
3118 | If thoughts ARE causal, we can't explain how they cause things [Segal] |
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] |
5457 | Predicates assert properties, values, denials, relations, conventions, existence and fabrications [Ellis, by PG] |
5488 | Regularity theories of causation cannot give an account of human agency [Ellis] |
5489 | Humans have variable dispositions, and also power to change their dispositions [Ellis] |
5490 | Essentialism fits in with Darwinism, but not with extreme politics of left or right [Ellis] |
5472 | Natural kinds are of objects/substances, or events/processes, or intrinsic natures [Ellis] |
5471 | Essentialism says natural kinds are fundamental to nature, and determine the laws [Ellis] |
5446 | For essentialists two members of a natural kind must be identical [Ellis] |
5480 | The whole of our world is a natural kind, so all worlds like it necessarily have the same laws [Ellis] |
5445 | Essentialists regard inanimate objects as genuine causal agents [Ellis] |
5463 | Essentialists believe causation is necessary, resulting from dispositions and circumstances [Ellis] |
5491 | A general theory of causation is only possible in an area if natural kinds are involved [Ellis] |
5442 | For 'passivists' behaviour is imposed on things from outside [Ellis] |
5473 | The laws of nature imitate the hierarchy of natural kinds [Ellis] |
5474 | Laws of nature tend to describe ideal things, or ideal circumstances [Ellis] |
5475 | We must explain the necessity, idealisation, ontology and structure of natural laws [Ellis] |
5460 | Causal relations cannot be reduced to regularities, as they could occur just once [Ellis] |
5459 | Essentialists say dispositions are basic, rather than supervenient on matter and natural laws [Ellis] |
5461 | The essence of uranium is its atomic number and its electron shell [Ellis] |
5464 | For essentialists, laws of nature are metaphysically necessary, being based on essences of natural kinds [Ellis] |
5487 | Essentialism requires a clear separation of semantics, epistemology and ontology [Ellis] |
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] |