18 ideas
| 18261 | A simplification which is complete constitutes a definition [Kant] |
| 10282 | Logic is the study of sound argument, or of certain artificial languages (or applying the latter to the former) [Hodges,W] |
| 22275 | Logic gives us the necessary rules which show us how we ought to think [Kant] |
| 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] |
| 3978 | Associations are held to connect Ideas together in the way the world is connected together [Fodor] |
| 18260 | If we knew what we know, we would be astonished [Kant] |
| 3976 | Intentional science needs objects with semantic and causal properties, and which obey laws [Fodor] |
| 3980 | Intentional states and processes may be causal relations among mental symbols [Fodor] |
| 3981 | Most psychological properties seem to be multiply realisable [Fodor] |
| 3975 | Folk psychology explains behaviour by reference to intentional states like belief and desire [Fodor] |
| 3982 | How could the extrinsic properties of thoughts supervene on their intrinsic properties? [Fodor] |
| 3977 | Laws are true generalisations which support counterfactuals and are confirmed by instances [Fodor] |