35 ideas
| 5750 | Consistency is modal, saying propositions are consistent if they could be true together [Melia] |
| 22285 | Impredicative definitions are circular, but fine for picking out, rather than creating something [Potter] |
| 22301 | The Identity Theory says a proposition is true if it coincides with what makes it true [Potter] |
| 22324 | It has been unfortunate that externalism about truth is equated with correspondence [Potter] |
| 5737 | Predicate logic has connectives, quantifiers, variables, predicates, equality, names and brackets [Melia] |
| 5744 | First-order predicate calculus is extensional logic, but quantified modal logic is intensional (hence dubious) [Melia] |
| 22279 | Frege's sign |--- meant judgements, but the modern |- turnstile means inference, with intecedents [Potter] |
| 22291 | Deductivism can't explain how the world supports unconditional conclusions [Potter] |
| 5740 | Second-order logic needs second-order variables and quantification into predicate position [Melia] |
| 22295 | Modern logical truths are true under all interpretations of the non-logical words [Potter] |
| 5741 | If every model that makes premises true also makes conclusion true, the argument is valid [Melia] |
| 22310 | The formalist defence against Gödel is to reject his metalinguistic concept of truth [Potter] |
| 22298 | Why is fictional arithmetic applicable to the real world? [Potter] |
| 22287 | If 'concrete' is the negative of 'abstract', that means desires and hallucinations are concrete [Potter] |
| 5736 | No sort of plain language or levels of logic can express modal facts properly [Melia] |
| 5735 | Maybe names and predicates can capture any fact [Melia] |
| 22284 | 'Greater than', which is the ancestral of 'successor', strictly orders the natural numbers [Potter] |
| 5746 | The Identity of Indiscernibles is contentious for qualities, and trivial for non-qualities [Melia] |
| 5738 | We may be sure that P is necessary, but is it necessarily necessary? [Melia] |
| 5732 | 'De re' modality is about things themselves, 'de dicto' modality is about propositions [Melia] |
| 5739 | Sometimes we want to specify in what ways a thing is possible [Melia] |
| 22281 | A material conditional cannot capture counterfactual reasoning [Potter] |
| 5734 | Possible worlds make it possible to define necessity and counterfactuals without new primitives [Melia] |
| 5742 | In possible worlds semantics the modal operators are treated as quantifiers [Melia] |
| 5743 | If possible worlds semantics is not realist about possible worlds, logic becomes merely formal [Melia] |
| 5749 | Possible worlds could be real as mathematics, propositions, properties, or like books [Melia] |
| 5751 | The truth of propositions at possible worlds are implied by the world, just as in books [Melia] |
| 22327 | Knowledge from a drunken schoolteacher is from a reliable and unreliable process [Potter] |
| 22273 | Traditionally there are twelve categories of judgement, in groups of three [Potter] |
| 22290 | The phrase 'the concept "horse"' can't refer to a concept, because it is saturated [Potter] |
| 5748 | We accept unverifiable propositions because of simplicity, utility, explanation and plausibility [Melia] |
| 22283 | Compositionality should rely on the parsing tree, which may contain more than sentence components [Potter] |
| 22282 | 'Direct compositonality' says the components wholly explain a sentence meaning [Potter] |
| 22296 | Compositionality is more welcome in logic than in linguistics (which is more contextual) [Potter] |
| 468 | Musical performance can reveal a range of virtues [Damon of Ath.] |