63 ideas
| 8605 | In addition to analysis of a concept, one can deny it, or accept it as primitive [Lewis] |
| 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] |
| 8607 | Supervenience is reduction without existence denials, ontological priorities, or translatability [Lewis] |
| 8606 | A supervenience thesis is a denial of independent variation [Lewis] |
| 8580 | Materialism is (roughly) that two worlds cannot differ without differing physically [Lewis] |
| 15538 | Semantic indecision explains vagueness (if we have precisifications to be undecided about) [Lewis] |
| 8571 | Universals are wholly present in their instances, whereas properties are spread around [Lewis] |
| 10717 | Natural properties figure in the analysis of similarity in intrinsic respects [Lewis, by Oliver] |
| 16217 | Lewisian natural properties fix reference of predicates, through a principle of charity [Lewis, by Hawley] |
| 8613 | Objects are demarcated by density and chemistry, and natural properties belong in what is well demarcated [Lewis] |
| 8585 | Reference partly concerns thought and language, partly eligibility of referent by natural properties [Lewis] |
| 8586 | Natural properties tend to belong to well-demarcated things, typically loci of causal chains [Lewis] |
| 8589 | For us, a property being natural is just an aspect of its featuring in the contents of our attitudes [Lewis] |
| 15460 | All perfectly natural properties are intrinsic [Lewis, by Lewis] |
| 15726 | Natural properties fix resemblance and powers, and are picked out by universals [Lewis] |
| 7031 | Lewis says properties are sets of actual and possible objects [Lewis, by Heil] |
| 8572 | Any class of things is a property, no matter how whimsical or irrelevant [Lewis] |
| 18433 | There are far more properties than any brain could ever encodify [Lewis] |
| 8604 | We need properties as semantic values for linguistic expressions [Lewis] |
| 14499 | Properties are classes of possible and actual concrete particulars [Lewis, by Koslicki] |
| 15120 | Lewisian properties have powers because of their relationships to other properties [Lewis, by Hawthorne] |
| 8573 | Most properties are causally irrelevant, and we can't spot the relevant ones. [Lewis] |
| 8569 | I suspend judgements about universals, but their work must be done [Lewis] |
| 21961 | Physics aims to discover which universals actually exist [Lewis, by Moore,AW] |
| 8576 | The One over Many problem (in predication terms) deserves to be neglected (by ostriches) [Lewis] |
| 8570 | To have a property is to be a member of a class, usually a class of things [Lewis] |
| 8574 | Class Nominalism and Resemblance Nominalism are pretty much the same [Lewis] |
| 15537 | If cats are vague, we deny that the many cats are one, or deny that the one cat is many [Lewis] |
| 15536 | We have one cloud, but many possible boundaries and aggregates for it [Lewis] |
| 12033 | An object is identical with itself, and no different indiscernible object can share that [Russell/Whitehead, by Adams,RM] |
| 10040 | Russell showed, through the paradoxes, that our basic logical intuitions are self-contradictory [Russell/Whitehead, by Gödel] |
| 8579 | Psychophysical identity implies the possibility of idealism or panpsychism [Lewis] |
| 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] |
| 23453 | Propositions as objects of judgement don't exist, because we judge several objects, not one [Russell/Whitehead] |
| 8614 | A sophisticated principle of charity sometimes imputes error as well as truth [Lewis] |
| 8615 | We need natural properties in order to motivate the principle of charity [Lewis] |
| 15539 | Basic to pragmatics is taking a message in a way that makes sense of it [Lewis] |
| 8608 | Counterfactuals 'backtrack' if a different present implies a different past [Lewis] |
| 8584 | Causal counterfactuals must avoid backtracking, to avoid epiphenomena and preemption [Lewis] |
| 8581 | Physics discovers laws and causal explanations, and also the natural properties required [Lewis] |
| 15727 | Physics aims for a list of natural properties [Lewis] |
| 8611 | A law of nature is any regularity that earns inclusion in the ideal system [Lewis] |