74 ideas
7973 | There is no longer anything on which there is nothing to say [Baudrillard] |
7975 | The task of philosophy is to unmask the illusion of objective reality [Baudrillard] |
7986 | Drunken boat pilots are less likely to collide than clearly focused ones [Baudrillard] |
7982 | Instead of thesis and antithesis leading to synthesis, they now cancel out, and the conflict is levelled [Baudrillard] |
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] |
10111 | Asserting Excluded Middle is a hallmark of realism about the natural world [George/Velleman] |
15592 | The usual Tarskian interpretation of variables is to specify their range of values [Fine,K] |
15593 | Variables can be viewed as special terms - functions taking assignments into individuals [Fine,K] |
15590 | It seemed that Frege gave the syntax for variables, and Tarski the semantics, and that was that [Fine,K] |
15591 | In separate expressions variables seem identical in role, but in the same expression they aren't [Fine,K] |
15595 | The 'algebraic' account of variables reduces quantification to the algebra of its component parts [Fine,K] |
15594 | 'Instantial' accounts of variables say we grasp arbitrary instances from their use in quantification [Fine,K] |
15599 | Cicero/Cicero and Cicero/Tully may differ in relationship, despite being semantically the same [Fine,K] |
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] |
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] |
17901 | Type theory prohibits (oddly) a set containing an individual and a set of individuals [George/Velleman] |
10114 | Bounded quantification is originally finitary, as conjunctions and disjunctions [George/Velleman] |
10134 | Much infinite mathematics can still be justified finitely [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] |
7974 | Without God we faced reality: what do we face without reality? [Baudrillard] |
7987 | Nothing is true, but everything is exact [Baudrillard] |
15603 | I can only represent individuals as the same if I do not already represent them as the same [Fine,K] |
15604 | If Cicero=Tully refers to the man twice, then surely Cicero=Cicero does as well? [Fine,K] |
7978 | There is no need to involve the idea of free will to make choices about one's life [Baudrillard] |
15602 | Mental files are devices for keeping track of basic coordination of objects [Fine,K] |
15588 | You cannot determine the full content from a thought's intrinsic character, as relations are involved [Fine,K] |
10110 | Corresponding to every concept there is a class (some of them sets) [George/Velleman] |
15596 | The standard aim of semantics is to assign a semantic value to each expression [Fine,K] |
15587 | That two utterances say the same thing may not be intrinsic to them, but involve their relationships [Fine,K] |
15589 | The two main theories are Holism (which is inferential), and Representational (which is atomistic) [Fine,K] |
15598 | We should pursue semantic facts as stated by truths in theories (and not put the theories first!) [Fine,K] |
15600 | Referentialist semantics has objects for names, properties for predicates, and propositions for connectives [Fine,K] |
15601 | Fregeans approach the world through sense, Referentialists through reference [Fine,K] |
15605 | I take indexicals such as 'this' and 'that' to be linked to some associated demonstration [Fine,K] |
7980 | In modern times, being useless is the essential aesthetic ingredient for an object [Baudrillard] |
7983 | Good versus evil has been banefully reduced to happiness versus misfortune [Baudrillard] |
7981 | Whole populations are terrorist threats to authorities, who unite against them [Baudrillard] |
7976 | People like democracy because it means they can avoid power [Baudrillard] |
7977 | Only in the last 200 years have people demanded the democratic privilege of being individuals [Baudrillard] |
7979 | The arrival of the news media brought history to an end [Baudrillard] |
7984 | Suicide is ascribed to depression, with the originality of the act of will ignored [Baudrillard] |
7985 | Pascal says secular life is acceptable, but more fun with the hypothesis of God [Baudrillard] |