46 ideas
13252 | Some truths have true negations [Beall/Restall] |
13247 | A truthmaker is an object which entails a sentence [Beall/Restall] |
7689 | The modal logic of C.I.Lewis was only interpreted by Kripke and Hintikka in the 1960s [Jacquette] |
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] |
13246 | Relevant logic does not abandon classical logic [Beall/Restall] |
13245 | Relevant consequence says invalidity is the conclusion not being 'in' the premises [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] |
7681 | Logic describes inferences between sentences expressing possible properties of objects [Jacquette] |
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13234 | The view of logic as knowing a body of truths looks out-of-date [Beall/Restall] |
16728 | Logicians acknowledge too few things, while others acknowledge too many [Fitzralph] |
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] |
7682 | Logic is not just about signs, because it relates to states of affairs, objects, properties and truth-values [Jacquette] |
7697 | On Russell's analysis, the sentence "The winged horse has wings" comes out as false [Jacquette] |
13236 | Logical truth is much more important if mathematics rests on it, as logicism claims [Beall/Restall] |
7701 | Can a Barber shave all and only those persons who do not shave themselves? [Jacquette] |
13237 | Preface Paradox affirms and denies the conjunction of propositions in the book [Beall/Restall] |
7707 | To grasp being, we must say why something exists, and why there is one world [Jacquette] |
7692 | Being is maximal consistency [Jacquette] |
7687 | Existence is completeness and consistency [Jacquette] |
7679 | Ontology is the same as the conceptual foundations of logic [Jacquette] |
7678 | Ontology must include the minimum requirements for our semantics [Jacquette] |
7683 | Logic is based either on separate objects and properties, or objects as combinations of properties [Jacquette] |
7684 | Reduce states-of-affairs to object-property combinations, and possible worlds to states-of-affairs [Jacquette] |
7703 | If classes can't be eliminated, and they are property combinations, then properties (universals) can't be either [Jacquette] |
7685 | An object is a predication subject, distinguished by a distinctive combination of properties [Jacquette] |
7699 | Numbers, sets and propositions are abstract particulars; properties, qualities and relations are universals [Jacquette] |
13244 | Relevant necessity is always true for some situation (not all situations) [Beall/Restall] |
7691 | The actual world is a consistent combination of states, made of consistent property combinations [Jacquette] |
7688 | The actual world is a maximally consistent combination of actual states of affairs [Jacquette] |
7695 | Do proposition-structures not associated with the actual world deserve to be called worlds? [Jacquette] |
7694 | We must experience the 'actual' world, which is defined by maximally consistent propositions [Jacquette] |
7706 | If qualia supervene on intentional states, then intentional states are explanatorily fundamental [Jacquette] |
7704 | Reduction of intentionality involving nonexistent objects is impossible, as reduction must be to what is actual [Jacquette] |
13239 | Judgement is always predicating a property of a subject [Beall/Restall] |
13248 | We can rest truth-conditions on situations, rather than on possible worlds [Beall/Restall] |
7702 | The extreme views on propositions are Frege's Platonism and Quine's extreme nominalism [Jacquette] |
13233 | Propositions commit to content, and not to any way of spelling it out [Beall/Restall] |