34 ideas
2666 | Carneades' pinnacles of philosophy are the basis of knowledge (the criterion of truth) and the end of appetite (good) [Carneades, by Cicero] |
10476 | The idea that groups of concepts could be 'implicitly defined' was abandoned [Hodges,W] |
21390 | Future events are true if one day we will say 'this event is happening now' [Carneades] |
21672 | We say future things are true that will possess actuality at some following time [Carneades, by Cicero] |
10282 | Logic is the study of sound argument, or of certain artificial languages (or applying the latter to the former) [Hodges,W] |
10478 | Since first-order languages are complete, |= and |- have the same meaning [Hodges,W] |
10477 | |= in model-theory means 'logical consequence' - it holds in all models [Hodges,W] |
7760 | Russell only uses descriptions attributively, and Strawson only referentially [Donnellan, by Lycan] |
5811 | A definite description can have a non-referential use [Donnellan] |
5812 | Definite descriptions are 'attributive' if they say something about x, and 'referential' if they pick x out [Donnellan] |
5814 | 'The x is F' only presumes that x exists; it does not actually entail the existence [Donnellan] |
10284 | There are three different standard presentations of semantics [Hodges,W] |
10283 | A formula needs an 'interpretation' of its constants, and a 'valuation' of its variables [Hodges,W] |
10285 | I |= φ means that the formula φ is true in the interpretation I [Hodges,W] |
10474 | |= should be read as 'is a model for' or 'satisfies' [Hodges,W] |
10473 | Model theory studies formal or natural language-interpretation using set-theory [Hodges,W] |
10475 | A 'structure' is an interpretation specifying objects and classes of quantification [Hodges,W] |
10481 | Models in model theory are structures, not sets of descriptions [Hodges,W] |
10289 | Up Löwenheim-Skolem: if infinite models, then arbitrarily large models [Hodges,W] |
10288 | Down Löwenheim-Skolem: if a countable language has a consistent theory, that has a countable model [Hodges,W] |
10287 | If a first-order theory entails a sentence, there is a finite subset of the theory which entails it [Hodges,W] |
10480 | First-order logic can't discriminate between one infinite cardinal and another [Hodges,W] |
10286 | A 'set' is a mathematically well-behaved class [Hodges,W] |
15825 | Carneades denied the transitivity of identity [Carneades, by Chisholm] |
21389 | Carneades distinguished logical from causal necessity, when talking of future events [Long on Carneades] |
21671 | Voluntary motion is intrinsically within our power, and this power is its cause [Carneades, by Cicero] |
21391 | Some actions are within our power; determinism needs prior causes for everything - so it is false [Carneades, by Cicero] |
21674 | Even Apollo can only foretell the future when it is naturally necessary [Carneades, by Cicero] |
10435 | A definite description 'the F' is referential if the speaker could thereby be referring to something not-F [Donnellan, by Sainsbury] |
10451 | Donnellan is unclear whether the referential-attributive distinction is semantic or pragmatic [Bach on Donnellan] |
5813 | A description can successfully refer, even if its application to the subject is not believed [Donnellan] |
5815 | Whether a definite description is referential or attributive depends on the speaker's intention [Donnellan] |
7398 | Carneades said that after a shipwreck a wise man would seize the only plank by force [Carneades, by Tuck] |
21392 | People change laws for advantage; either there is no justice, or it is a form of self-injury [Carneades, by Lactantius] |