27 ideas
2510 | Traditionally philosophy is an a priori enquiry into general truths about reality [Katz] |
2516 | Most of philosophy begins where science leaves off [Katz] |
10282 | Logic is the study of sound argument, or of certain artificial languages (or applying the latter to the former) [Hodges,W] |
10283 | A formula needs an 'interpretation' of its constants, and a 'valuation' of its variables [Hodges,W] |
10284 | There are three different standard presentations of semantics [Hodges,W] |
10285 | I |= φ means that the formula φ is true in the interpretation I [Hodges,W] |
10288 | Down Löwenheim-Skolem: if a countable language has a consistent theory, that has a countable model [Hodges,W] |
10289 | Up Löwenheim-Skolem: if infinite models, then arbitrarily large models [Hodges,W] |
10287 | If a first-order theory entails a sentence, there is a finite subset of the theory which entails it [Hodges,W] |
10286 | A 'set' is a mathematically well-behaved class [Hodges,W] |
2521 | 'Real' maths objects have no causal role, no determinate reference, and no abstract/concrete distinction [Katz] |
2513 | We don't have a clear enough sense of meaning to pronounce some sentences meaningless or just analytic [Katz] |
2522 | Experience cannot teach us why maths and logic are necessary [Katz] |
2517 | Structuralists see meaning behaviouristically, and Chomsky says nothing about it [Katz] |
2519 | It is generally accepted that sense is defined as the determiner of reference [Katz] |
2520 | Sense determines meaning and synonymy, not referential properties like denotation and truth [Katz] |
2518 | Sentences are abstract types (like musical scores), not individual tokens [Katz] |
2705 | How can intuitionists distinguish universal convictions from local cultural ones? [Hare] |
2712 | You can't use intuitions to decide which intuitions you should cultivate [Hare] |
2706 | Emotivists mistakenly think all disagreements are about facts, and so there are no moral reasons [Hare] |
2709 | Prescriptivism sees 'ought' statements as imperatives which are universalisable [Hare] |
2704 | If morality is just a natural or intuitive description, that leads to relativism [Hare] |
2703 | Descriptivism say ethical meaning is just truth-conditions; prescriptivism adds an evaluation [Hare] |
2707 | If there can be contradictory prescriptions, then reasoning must be involved [Hare] |
2708 | An 'ought' statement implies universal application [Hare] |
2711 | Prescriptivism implies a commitment, but descriptivism doesn't [Hare] |
2710 | Moral judgements must invoke some sort of principle [Hare] |