25 ideas
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] |
8250 | So-called 'free logic' operates without existence assumptions [Meinong, by George/Van Evra] |
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] |
8719 | There can be impossible and contradictory objects, if they can have properties [Meinong, by Friend] |
8971 | There are objects of which it is true that there are no such objects [Meinong] |
8718 | Meinong says an object need not exist, but must only have properties [Meinong, by Friend] |
7756 | Meinong said all objects of thought (even self-contradictions) have some sort of being [Meinong, by Lycan] |
15781 | The objects of knowledge are far more numerous than objects which exist [Meinong] |
7800 | Analytic truths are divided into logically and conceptually necessary [Girle] |
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] |
3488 | Freud treats the unconscious as intentional and hence mental [Freud, by Searle] |
5689 | Freud and others have shown that we don't know our own beliefs, feelings, motive and attitudes [Freud, by Shoemaker] |
23950 | Freud said passions are pressures of some flowing hydraulic quantity [Freud, by Solomon] |
22344 | Freud is pessimistic about human nature; it is ambivalent motive and fantasy, rather than reason [Freud, by Murdoch] |