13 ideas
| 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] |
| 8872 | It is widely supposed that externalism cannot be reconciled with first-person authority [Davidson] |
| 8874 | It is hard to interpret a speaker's actions if we take a broad view of the content [Davidson] |
| 13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
| 8873 | The cause of a usage determines meaning, but why is the microstructure of water relevant? [Davidson] |
| 20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |