19 ideas
6859 | Analytic philosophy has much higher standards of thinking than continental philosophy [Williamson] |
6862 | Fuzzy logic uses a continuum of truth, but it implies contradictions [Williamson] |
10301 | The axiom of choice is controversial, but it could be replaced [Shapiro] |
6858 | Formal logic struck me as exactly the language I wanted to think in [Williamson] |
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] |
10590 | Up Löwenheim-Skolem: if natural numbers satisfy wffs, then an infinite domain satisfies them [Shapiro] |
10296 | The Löwenheim-Skolem Theorems fail for second-order languages with standard semantics [Shapiro] |
10297 | The Löwenheim-Skolem theorem seems to be a defect of first-order logic [Shapiro] |
10292 | Downward Löwenheim-Skolem: if there's an infinite model, there is a countable model [Shapiro] |
10294 | Second-order logic has the expressive power for mathematics, but an unworkable model theory [Shapiro] |
6863 | Close to conceptual boundaries judgement is too unreliable to give knowledge [Williamson] |
10591 | Logicians use 'property' and 'set' interchangeably, with little hanging on it [Shapiro] |
6861 | What sort of logic is needed for vague concepts, and what sort of concept of truth? [Williamson] |
6860 | How can one discriminate yellow from red, but not the colours in between? [Williamson] |
22489 | 'Good' is an attributive adjective like 'large', not predicative like 'red' [Geach, by Foot] |