47 ideas
9542 | The best known axiomatization of PL is Whitehead/Russell, with four axioms and two rules [Russell/Whitehead, by Hughes/Cresswell] |
21720 | Russell saw Reducibility as legitimate for reducing classes to logic [Linsky,B on Russell/Whitehead] |
10044 | Russell denies extensional sets, because the null can't be a collection, and the singleton is just its element [Russell/Whitehead, by Shapiro] |
18208 | We regard classes as mere symbolic or linguistic conveniences [Russell/Whitehead] |
8204 | Lewis's 'strict implication' preserved Russell's confusion of 'if...then' with implication [Quine on Russell/Whitehead] |
9359 | Russell's implication means that random sentences imply one another [Lewis,CI on Russell/Whitehead] |
21707 | Russell unusually saw logic as 'interpreted' (though very general, and neutral) [Russell/Whitehead, by Linsky,B] |
10036 | In 'Principia' a new abstract theory of relations appeared, and was applied [Russell/Whitehead, by Gödel] |
18248 | A real number is the class of rationals less than the number [Russell/Whitehead, by Shapiro] |
18152 | Russell takes numbers to be classes, but then reduces the classes to numerical quantifiers [Russell/Whitehead, by Bostock] |
10025 | Russell and Whitehead took arithmetic to be higher-order logic [Russell/Whitehead, by Hodes] |
8683 | Russell and Whitehead were not realists, but embraced nearly all of maths in logic [Russell/Whitehead, by Friend] |
10037 | 'Principia' lacks a precise statement of the syntax [Gödel on Russell/Whitehead] |
10093 | The ramified theory of types used propositional functions, and covered bound variables [Russell/Whitehead, by George/Velleman] |
8691 | The Russell/Whitehead type theory was limited, and was not really logic [Friend on Russell/Whitehead] |
10305 | In 'Principia Mathematica', logic is exceeded in the axioms of infinity and reducibility, and in the domains [Bernays on Russell/Whitehead] |
8684 | Russell and Whitehead consider the paradoxes to indicate that we create mathematical reality [Russell/Whitehead, by Friend] |
8746 | To avoid vicious circularity Russell produced ramified type theory, but Ramsey simplified it [Russell/Whitehead, by Shapiro] |
12033 | An object is identical with itself, and no different indiscernible object can share that [Russell/Whitehead, by Adams,RM] |
14703 | Superficial necessity is true in all worlds; deep necessity is thus true, no matter which world is actual [Schroeter] |
14714 | Contradictory claims about a necessary god both seem apriori coherent [Schroeter] |
14704 | 2D semantics gives us apriori knowledge of our own meanings [Schroeter] |
10040 | Russell showed, through the paradoxes, that our basic logical intuitions are self-contradictory [Russell/Whitehead, by Gödel] |
21725 | The multiple relations theory says assertions about propositions are about their ingredients [Russell/Whitehead, by Linsky,B] |
23474 | A judgement is a complex entity, of mind and various objects [Russell/Whitehead] |
23455 | The meaning of 'Socrates is human' is completed by a judgement [Russell/Whitehead] |
23480 | The multiple relation theory of judgement couldn't explain the unity of sentences [Morris,M on Russell/Whitehead] |
18275 | Only the act of judging completes the meaning of a statement [Russell/Whitehead] |
14706 | Your view of water depends on whether you start from the actual Earth or its counterfactual Twin [Schroeter] |
14711 | Rationalists say knowing an expression is identifying its extension using an internal cognitive state [Schroeter] |
14717 | Internalist meaning is about understanding; externalist meaning is about embedding in a situation [Schroeter] |
14720 | Semantic theory assigns meanings to expressions, and metasemantics explains how this works [Schroeter] |
14695 | Semantic theories show how truth of sentences depends on rules for interpreting and joining their parts [Schroeter] |
14696 | Simple semantics assigns extensions to names and to predicates [Schroeter] |
14697 | 'Federer' and 'best tennis player' can't mean the same, despite having the same extension [Schroeter] |
14698 | Possible worlds semantics uses 'intensions' - functions which assign extensions at each world [Schroeter] |
14699 | Possible worlds make 'I' and that person's name synonymous, but they have different meanings [Schroeter] |
14709 | Possible worlds semantics implies a constitutive connection between meanings and modal claims [Schroeter] |
14719 | In the possible worlds account all necessary truths are same (because they all map to the True) [Schroeter] |
14701 | Array worlds along the horizontal, and contexts (world,person,time) along the vertical [Schroeter] |
14702 | If we introduce 'actually' into modal talk, we need possible worlds twice to express this [Schroeter] |
14705 | Do we know apriori how we refer to names and natural kinds, but their modal profiles only a posteriori? [Schroeter] |
14715 | 2D fans defend it for conceptual analysis, for meaning, and for internalist reference [Schroeter] |
14716 | 2D semantics can't respond to contingent apriori claims, since there is no single proposition involved [Schroeter] |
23453 | Propositions as objects of judgement don't exist, because we judge several objects, not one [Russell/Whitehead] |
13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |