45 ideas
| 16512 | Semantic facts are preferable to transcendental philosophical fiction [Wiggins] |
| 7786 | Propositional logic handles negation, disjunction, conjunction; predicate logic adds quantifiers, predicates, relations [Girle] |
| 7798 | There are three axiom schemas for propositional logic [Girle] |
| 7799 | Proposition logic has definitions for its three operators: or, and, and identical [Girle] |
| 7797 | Axiom systems of logic contain axioms, inference rules, and definitions of proof and theorems [Girle] |
| 7794 | There are seven modalities in S4, each with its negation [Girle] |
| 7793 | ◊p → □◊p is the hallmark of S5 [Girle] |
| 7795 | S5 has just six modalities, and all strings can be reduced to those [Girle] |
| 7787 | Possible worlds logics use true-in-a-world rather than true [Girle] |
| 7788 | Modal logic has four basic modal negation equivalences [Girle] |
| 7796 | Modal logics were studied in terms of axioms, but now possible worlds semantics is added [Girle] |
| 7789 | Necessary implication is called 'strict implication'; if successful, it is called 'entailment' [Girle] |
| 7790 | If an argument is invalid, a truth tree will indicate a counter-example [Girle] |
| 17529 | Maybe the concept needed under which things coincide must also yield a principle of counting [Wiggins] |
| 17530 | The sortal needed for identities may not always be sufficient to support counting [Wiggins] |
| 16523 | Realist Conceptualists accept that our interests affect our concepts [Wiggins] |
| 16524 | Conceptualism says we must use our individuating concepts to grasp reality [Wiggins] |
| 16526 | Animal classifications: the Emperor's, fabulous, innumerable, like flies, stray dogs, embalmed…. [Wiggins] |
| 16492 | Individuation needs accounts of identity, of change, and of singling out [Wiggins] |
| 16493 | Individuation can only be understood by the relation between things and thinkers [Wiggins] |
| 16496 | Singling out extends back and forward in time [Wiggins] |
| 16495 | The only singling out is singling out 'as' something [Wiggins] |
| 16501 | In Aristotle's sense, saying x falls under f is to say what x is [Wiggins] |
| 16506 | Every determinate thing falls under a sortal, which fixes its persistence [Wiggins] |
| 16509 | Natural kinds are well suited to be the sortals which fix substances [Wiggins] |
| 16514 | Artefacts are individuated by some matter having a certain function [Wiggins] |
| 16510 | Nominal essences don't fix membership, ignore evolution, and aren't contextual [Wiggins] |
| 16503 | 'What is it?' gives the kind, nature, persistence conditions and identity over time of a thing [Wiggins] |
| 16499 | A restored church is the same 'church', but not the same 'building' or 'brickwork' [Wiggins] |
| 16515 | A thing begins only once; for a clock, it is when its making is first completed [Wiggins] |
| 16517 | Priests prefer the working ship; antiquarians prefer the reconstruction [Wiggins] |
| 16498 | Identity cannot be defined, because definitions are identities [Wiggins] |
| 16497 | Leibniz's Law (not transitivity, symmetry, reflexivity) marks what is peculiar to identity [Wiggins] |
| 16502 | Identity is primitive [Wiggins] |
| 16521 | A is necessarily A, so if B is A, then B is also necessarily A [Wiggins] |
| 16505 | By the principle of Indiscernibility, a symmetrical object could only be half of itself! [Wiggins] |
| 16494 | We want to explain sameness as coincidence of substance, not as anything qualitative [Wiggins] |
| 7800 | Analytic truths are divided into logically and conceptually necessary [Girle] |
| 7801 | Possibilities can be logical, theoretical, physical, economic or human [Girle] |
| 16522 | It is hard or impossible to think of Caesar as not human [Wiggins] |
| 7792 | A world has 'access' to a world it generates, which is important in possible worlds semantics [Girle] |
| 16525 | Our sortal concepts fix what we find in experience [Wiggins] |
| 16518 | We conceptualise objects, but they impinge on us [Wiggins] |
| 16511 | A 'conception' of a horse is a full theory of what it is (and not just the 'concept') [Wiggins] |
| 4422 | The end need not be the goal, as in the playing of a melody (and yet it must be completed) [Nietzsche] |