28 ideas
1708 | In "Callias is just/not just/unjust", which of these are contraries? [Aristotle] |
1703 | It is necessary that either a sea-fight occurs tomorrow or it doesn't, though neither option is in itself necessary [Aristotle] |
1704 | Statements are true according to how things actually are [Aristotle] |
22272 | Aristotle's later logic had to treat 'Socrates' as 'everything that is Socrates' [Potter on Aristotle] |
9405 | Square of Opposition: not both true, or not both false; one-way implication; opposite truth-values [Aristotle] |
9730 | Modal Square 3: □P and ¬◊¬P are 'contradictories' of ¬□P and ◊¬P [Aristotle, by Fitting/Mendelsohn] |
9728 | Modal Square 1: □P and ¬◊¬P are 'contraries' of □¬P and ¬◊P [Aristotle, by Fitting/Mendelsohn] |
9729 | Modal Square 2: ¬□¬P and ◊P are 'subcontraries' of ¬□P and ◊¬P [Aristotle, by Fitting/Mendelsohn] |
9731 | Modal Square 4: □¬P and ¬◊P are 'contradictories' of ¬□¬P and ◊P [Aristotle, by Fitting/Mendelsohn] |
9732 | Modal Square 5: □P and ¬◊¬P are 'subalternatives' of ¬□¬P and ◊P [Aristotle, by Fitting/Mendelsohn] |
9733 | Modal Square 6: □¬P and ¬◊P are 'subalternatives' of ¬□P and ◊¬P [Aristotle, by Fitting/Mendelsohn] |
10779 | A comprehension axiom is 'predicative' if the formula has no bound second-order variables [Linnebo] |
10781 | A 'pure logic' must be ontologically innocent, universal, and without presuppositions [Linnebo] |
21593 | In talking of future sea-fights, Aristotle rejects bivalence [Aristotle, by Williamson] |
1701 | A prayer is a sentence which is neither true nor false [Aristotle] |
10783 | Plural quantification depends too heavily on combinatorial and set-theoretic considerations [Linnebo] |
10778 | Can second-order logic be ontologically first-order, with all the benefits of second-order? [Linnebo] |
13472 | Hilbert aimed to eliminate number from geometry [Hilbert, by Hart,WD] |
9546 | Euclid axioms concerns possibilities of construction, but Hilbert's assert the existence of objects [Hilbert, by Chihara] |
18742 | Hilbert's formalisation revealed implicit congruence axioms in Euclid [Hilbert, by Horsten/Pettigrew] |
18217 | Hilbert's geometry is interesting because it captures Euclid without using real numbers [Hilbert, by Field,H] |
1706 | Non-existent things aren't made to exist by thought, because their non-existence is part of the thought [Aristotle] |
1707 | Maybe necessity and non-necessity are the first principles of ontology [Aristotle] |
10782 | The modern concept of an object is rooted in quantificational logic [Linnebo] |
2337 | For Aristotle meaning and reference are linked to concepts [Aristotle, by Putnam] |
13763 | Spoken sounds vary between people, but are signs of affections of soul, which are the same for all [Aristotle] |
1705 | It doesn't have to be the case that in opposed views one is true and the other false [Aristotle] |
1702 | Things may be necessary once they occur, but not be unconditionally necessary [Aristotle] |