29 ideas
19504 | My modus ponens might be your modus tollens [Pritchard,D] |
10301 | The axiom of choice is controversial, but it could be replaced [Shapiro] |
10588 | First-order logic is Complete, and Compact, with the Löwenheim-Skolem Theorems [Shapiro] |
10298 | Some say that second-order logic is mathematics, not logic [Shapiro] |
10299 | If the aim of logic is to codify inferences, second-order logic is useless [Shapiro] |
10300 | Logical consequence can be defined in terms of the logical terminology [Shapiro] |
10290 | Second-order variables also range over properties, sets, relations or functions [Shapiro] |
10297 | The Löwenheim-Skolem theorem seems to be a defect of first-order logic [Shapiro] |
10590 | Up Löwenheim-Skolem: if natural numbers satisfy wffs, then an infinite domain satisfies them [Shapiro] |
10292 | Downward Löwenheim-Skolem: if there's an infinite model, there is a countable model [Shapiro] |
10296 | The Löwenheim-Skolem Theorems fail for second-order languages with standard semantics [Shapiro] |
10294 | Second-order logic has the expressive power for mathematics, but an unworkable model theory [Shapiro] |
10591 | Logicians use 'property' and 'set' interchangeably, with little hanging on it [Shapiro] |
19503 | An improbable lottery win can occur in a nearby possible world [Pritchard,D] |
19505 | Moore begs the question, or just offers another view, or uses 'know' wrongly [Pritchard,D, by PG] |
19499 | We can have evidence for seeing a zebra, but no evidence for what is entailed by that [Pritchard,D] |
19500 | Favouring: an entailment will give better support for the first belief than reason to deny the second [Pritchard,D] |
19502 | Maybe knowledge just needs relevant discriminations among contrasting cases [Pritchard,D] |
19498 | Epistemic internalism usually says justification must be accessible by reflection [Pritchard,D] |
19506 | Externalism is better than internalism in dealing with radical scepticism [Pritchard,D] |
19496 | Disjunctivism says perceptual justification must be both factual and known by the agent [Pritchard,D] |
19497 | Metaphysical disjunctivism says normal perceptions and hallucinations are different experiences [Pritchard,D] |
19495 | Epistemic externalism struggles to capture the idea of epistemic responsibility [Pritchard,D] |
19501 | We assess error against background knowledge, but that is just what radical scepticism challenges [Pritchard,D] |
19507 | Radical scepticism is merely raised, and is not a response to worrying evidence [Pritchard,D] |
20440 | Art is a referential activity, hence indefinable, but it has a set of symptoms [Goodman] |
20439 | Artistic symbols are judged by the fruitfulness of their classifications [Goodman, by Giovannelli] |
20438 | A performance is only an instance of a work if there is not a single error [Goodman] |
20437 | A copy only becomes an 'instance' of an artwork if there is a system of notation [Goodman] |