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Ideas of Rod Girle, by Text

[New Zealand, fl. 2003, Professor at the University of Auckland]

2000 Modal Logics and Philosophy
1.1 p.1 Propositional logic handles negation, disjunction, conjunction; predicate logic adds quantifiers, predicates, relations
1.1 p.2 Possible worlds logics use true-in-a-world rather than true
1.2 p.3 Modal logic has four basic modal negation equivalences
1.2 p.7 Necessary implication is called 'strict implication'; if successful, it is called 'entailment'
1.4 p.8 If an argument is invalid, a truth tree will indicate a counter-example
2.1 p.13 The simplest of the logics based on possible worlds is Lewis's S5
3.2 p.29 A world has 'access' to a world it generates, which is important in possible worlds semantics
3.3 p.34 ◊p → □◊p is the hallmark of S5
3.5 p.46 S5 has just six modalities, and all strings can be reduced to those
3.5 p.46 There are seven modalities in S4, each with its negation
6.5 p.92 Modal logics were studied in terms of axioms, but now possible worlds semantics is added
6.5 p.92 There are three axiom schemas for propositional logic
6.5 p.92 Axiom systems of logic contain axioms, inference rules, and definitions of proof and theorems
6.5 p.94 Proposition logic has definitions for its three operators: or, and, and identical
7.3 p.114 Analytic truths are divided into logically and conceptually necessary
7.3 p.114 Possibilities can be logical, theoretical, physical, economic or human