38 ideas
3123 | Science is in the business of carving nature at the joints [Segal] |
3125 | Psychology studies the way rationality links desires and beliefs to causality [Segal] |
10476 | The idea that groups of concepts could be 'implicitly defined' was abandoned [Hodges,W] |
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] |
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] |
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] |
16062 | A necessary relation between fact-levels seems to be a further irreducible fact [Lynch/Glasgow] |
16061 | If some facts 'logically supervene' on some others, they just redescribe them, adding nothing [Lynch/Glasgow] |
16060 | Nonreductive materialism says upper 'levels' depend on lower, but don't 'reduce' [Lynch/Glasgow] |
16064 | The hallmark of physicalism is that each causal power has a base causal power under it [Lynch/Glasgow] |
3105 | Is 'Hesperus = Phosphorus' metaphysically necessary, but not logically or epistemologically necessary? [Segal] |
3106 | If claims of metaphysical necessity are based on conceivability, we should be cautious [Segal] |
3113 | The success and virtue of an explanation do not guarantee its truth [Segal] |
3112 | Folk psychology is ridiculously dualist in its assumptions [Segal] |
3108 | If 'water' has narrow content, it refers to both H2O and XYZ [Segal] |
3110 | Humans are made of H2O, so 'twins' aren't actually feasible [Segal] |
3124 | Externalists can't assume old words refer to modern natural kinds [Segal] |
3117 | Concepts can survive a big change in extension [Segal] |
3104 | Must we relate to some diamonds to understand them? [Segal] |
3103 | Maybe content involves relations to a language community [Segal] |
3111 | Externalism can't explain concepts that have no reference [Segal] |
3109 | If content is external, so are beliefs and desires [Segal] |
3116 | Maybe experts fix content, not ordinary users [Segal] |
3121 | If content is narrow, my perfect twin shares my concepts [Segal] |
3118 | If thoughts ARE causal, we can't explain how they cause things [Segal] |
3119 | Even 'mass' cannot be defined in causal terms [Segal] |