25 ideas
7798 | There are three axiom schemas for propositional logic [Girle] |
7786 | Propositional logic handles negation, disjunction, conjunction; predicate logic adds quantifiers, predicates, relations [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] |
17751 | Gödel proved the completeness of first order predicate logic in 1930 [Gödel, by Walicki] |
15163 | The interest of quantified modal logic is its metaphysical necessity and essentialism [Soames] |
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] |
7796 | Modal logics were studied in terms of axioms, but now possible worlds semantics is added [Girle] |
7788 | Modal logic has four basic modal negation equivalences [Girle] |
7789 | Necessary implication is called 'strict implication'; if successful, it is called 'entailment' [Girle] |
15158 | Indefinite descriptions are quantificational in subject position, but not in predicate position [Soames] |
15157 | Recognising the definite description 'the man' as a quantifier phrase, not a singular term, is a real insight [Soames] |
15156 | The universal and existential quantifiers were chosen to suit mathematics [Soames] |
7790 | If an argument is invalid, a truth tree will indicate a counter-example [Girle] |
7800 | Analytic truths are divided into logically and conceptually necessary [Girle] |
15161 | There are more metaphysically than logically necessary truths [Soames] |
15162 | We understand metaphysical necessity intuitively, from ordinary life [Soames] |
7801 | Possibilities can be logical, theoretical, physical, economic or human [Girle] |
7792 | A world has 'access' to a world it generates, which is important in possible worlds semantics [Girle] |
15152 | To study meaning, study truth conditions, on the basis of syntax, and representation by the parts [Soames] |
15153 | Tarski's account of truth-conditions is too weak to determine meanings [Soames] |
15154 | We should use cognitive states to explain representational propositions, not vice versa [Soames] |