27 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] |
6472 | Continuity is a sufficient criterion for the identity of a rock, but not for part of a smooth fluid [Russell] |
6473 | Physical things are series of appearances whose matter obeys physical laws [Russell] |
6465 | We need not deny substance, but there seems no reason to assert it [Russell] |
6471 | The assumption by physicists of permanent substance is not metaphysically legitimate [Russell] |
6466 | Where possible, logical constructions are to be substituted for inferred entities [Russell] |
6467 | No sensibile is ever a datum to two people at once [Russell] |
6483 | Russell held that we are aware of states of our own brain [Russell, by Robinson,H] |
8244 | Sense-data are qualities devoid of subjectivity, which are the basis of science [Russell, by Deleuze/Guattari] |
6462 | Sense-data are not mental, but are part of the subject-matter of physics [Russell] |
6463 | Sense-data are objects, and do not contain the subject as part, the way beliefs do [Russell] |
6464 | Sense-data are usually objects within the body, but are not part of the subject [Russell] |
6459 | We do not know whether sense-data exist as objects when they are not data [Russell] |
6460 | 'Sensibilia' are identical to sense-data, without actually being data for any mind [Russell] |
6461 | Ungiven sense-data can no more exist than unmarried husbands [Russell] |
6458 | Individuating sense-data is difficult, because they divide when closely attended to [Russell] |
6469 | Sense-data may be subjective, if closing our eyes can change them [Russell] |
7903 | The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna] |
6470 | Matter is the limit of appearances as distance from the object diminishes [Russell] |
6468 | There is 'private space', and there is also the 'space of perspectives' [Russell] |