39 ideas
6575 | Philosophy may never find foundations, and may undermine our lives in the process [Fogelin] |
6585 | Rationality is threatened by fear of inconsistency, illusions of absolutes or relativism, and doubt [Fogelin] |
6568 | A game can be played, despite having inconsistent rules [Fogelin] |
6557 | Humans may never be able to attain a world view which is both rich and consistent [Fogelin] |
6560 | The law of noncontradiction is traditionally the most basic principle of rationality [Fogelin] |
6565 | The law of noncontradiction makes the distinction between asserting something and denying it [Fogelin] |
10476 | The idea that groups of concepts could be 'implicitly defined' was abandoned [Hodges,W] |
6574 | Legal reasoning is analogical, not deductive [Fogelin] |
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] |
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] |
10474 | |= should be read as 'is a model for' or 'satisfies' [Hodges,W] |
10481 | Models in model theory are structures, not sets of descriptions [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] |
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] |
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] |
6582 | Conventions can only work if they are based on something non-conventional [Fogelin] |
6576 | My view is 'circumspect rationalism' - that only our intellect can comprehend the world [Fogelin] |
6589 | Knowledge is legitimate only if all relevant defeaters have been eliminated [Fogelin] |
6596 | For coherentists, circularity is acceptable if the circle is large, rich and coherent [Fogelin] |
6597 | A rule of justification might be: don't raise the level of scrutiny without a good reason [Fogelin] |
3061 | Anaxarchus said that he was not even sure that he knew nothing [Anaxarchus, by Diog. Laertius] |
6588 | Scepticism is cartesian (sceptical scenarios), or Humean (future), or Pyrrhonian (suspend belief) [Fogelin] |
6590 | Scepticism deals in remote possibilities that are ineliminable and set the standard very high [Fogelin] |
6583 | Radical perspectivism replaces Kant's necessary scheme with many different schemes [Fogelin] |
6555 | We are also irrational, with a unique ability to believe in bizarre self-created fictions [Fogelin] |
6605 | Critics must be causally entangled with their subject matter [Fogelin] |
6607 | The word 'beautiful', when deprived of context, is nearly contentless [Fogelin] |
6604 | Saying 'It's all a matter to taste' ignores the properties of the object discussed [Fogelin] |
6586 | Cynics are committed to morality, but disappointed or disgusted by human failings [Fogelin] |
6572 | Deterrence, prevention, rehabilitation and retribution can come into conflict in punishments [Fogelin] |
6573 | Retributivists say a crime can be 'paid for'; deterrentists still worry about potential victims [Fogelin] |