35 ideas
13252 | Some truths have true negations [Beall/Restall] |
13247 | A truthmaker is an object which entails a sentence [Beall/Restall] |
15544 | If what is actual might have been impossible, we need S4 modal logic [Armstrong, by Lewis] |
13249 | (∀x)(A v B) |- (∀x)A v (∃x)B) is valid in classical logic but invalid intuitionistically [Beall/Restall] |
13243 | Excluded middle must be true for some situation, not for all situations [Beall/Restall] |
13242 | It's 'relevantly' valid if all those situations make it true [Beall/Restall] |
13245 | Relevant consequence says invalidity is the conclusion not being 'in' the premises [Beall/Restall] |
13246 | Relevant logic does not abandon classical logic [Beall/Restall] |
13254 | A doesn't imply A - that would be circular [Beall/Restall] |
13255 | Relevant logic may reject transitivity [Beall/Restall] |
13250 | Free logic terms aren't existential; classical is non-empty, with referring names [Beall/Restall] |
13235 | Logic studies consequence; logical truths are consequences of everything, or nothing [Beall/Restall] |
13238 | Syllogisms are only logic when they use variables, and not concrete terms [Beall/Restall] |
13234 | The view of logic as knowing a body of truths looks out-of-date [Beall/Restall] |
13232 | Logic studies arguments, not formal languages; this involves interpretations [Beall/Restall] |
13241 | The model theory of classical predicate logic is mathematics [Beall/Restall] |
13253 | There are several different consequence relations [Beall/Restall] |
13240 | A sentence follows from others if they always model it [Beall/Restall] |
9148 | I think of variables as objects rather than as signs [Fine,K] |
13236 | Logical truth is much more important if mathematics rests on it, as logicism claims [Beall/Restall] |
13237 | Preface Paradox affirms and denies the conjunction of propositions in the book [Beall/Restall] |
7024 | Properties are universals, which are always instantiated [Armstrong, by Heil] |
9478 | Even if all properties are categorical, they may be denoted by dispositional predicates [Armstrong, by Bird] |
10729 | Universals explain resemblance and causal power [Armstrong, by Oliver] |
4031 | It doesn't follow that because there is a predicate there must therefore exist a property [Armstrong] |
10024 | The type-token distinction is the universal-particular distinction [Armstrong, by Hodes] |
10728 | A thing's self-identity can't be a universal, since we can know it a priori [Armstrong, by Oliver] |
13244 | Relevant necessity is always true for some situation (not all situations) [Beall/Restall] |
9152 | If green is abstracted from a thing, it is only seen as a type if it is common to many things [Fine,K] |
13239 | Judgement is always predicating a property of a subject [Beall/Restall] |
9149 | To obtain the number 2 by abstraction, we only want to abstract the distinctness of a pair of objects [Fine,K] |
9150 | We should define abstraction in general, with number abstraction taken as a special case [Fine,K] |
9146 | After abstraction all numbers seem identical, so only 0 and 1 will exist! [Fine,K] |
13248 | We can rest truth-conditions on situations, rather than on possible worlds [Beall/Restall] |
13233 | Propositions commit to content, and not to any way of spelling it out [Beall/Restall] |