19 ideas
18781 | Inconsistency doesn't prevent us reasoning about some system [Mares] |
21560 | Any linguistic expression may lack meaning when taken out of context [Russell] |
21561 | 'The number one is bald' or 'the number one is fond of cream cheese' are meaningless [Russell] |
18789 | Intuitionist logic looks best as natural deduction [Mares] |
18790 | Intuitionism as natural deduction has no rule for negation [Mares] |
18787 | Three-valued logic is useful for a theory of presupposition [Mares] |
18130 | Axiom of Reducibility: there is always a function of the lowest possible order in a given level [Russell, by Bostock] |
18793 | Material implication (and classical logic) considers nothing but truth values for implications [Mares] |
18784 | In classical logic the connectives can be related elegantly, as in De Morgan's laws [Mares] |
18786 | Excluded middle standardly implies bivalence; attacks use non-contradiction, De M 3, or double negation [Mares] |
18780 | Standard disjunction and negation force us to accept the principle of bivalence [Mares] |
18782 | The connectives are studied either through model theory or through proof theory [Mares] |
18783 | Many-valued logics lack a natural deduction system [Mares] |
18792 | Situation semantics for logics: not possible worlds, but information in situations [Mares] |
18785 | Consistency is semantic, but non-contradiction is syntactic [Mares] |
18788 | For intuitionists there are not numbers and sets, but processes of counting and collecting [Mares] |
21562 | There is no complexity without relations, so no propositions, and no truth [Russell] |
604 | Knowledge is mind and knowing 'cohabiting' [Lycophron, by Aristotle] |
18791 | In 'situation semantics' our main concepts are abstracted from situations [Mares] |