23 ideas
291 | Don't assume that wisdom is the automatic consequence of old age [Plato] |
12104 | All ideas must be understood historically [Comte] |
12105 | Our knowledge starts in theology, passes through metaphysics, and ends in positivism [Comte] |
12112 | Metaphysics is just the oversubtle qualification of abstract names for phenomena [Comte] |
12106 | Positivism gives up absolute truth, and seeks phenomenal laws, by reason and observation [Comte] |
12111 | Positivism is the final state of human intelligence [Comte] |
12114 | Science can drown in detail, so we need broad scientists (to keep out the metaphysicians) [Comte] |
12116 | Only positivist philosophy can terminate modern social crises [Comte] |
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] |
12108 | All real knowledge rests on observed facts [Comte] |
12109 | We must observe in order to form theories, but connected observations need prior theories [Comte] |
12107 | Positivism explains facts by connecting particular phenomena with general facts [Comte] |
12115 | Introspection is pure illusion; we can obviously observe everything except ourselves [Comte] |
293 | Being unafraid (perhaps through ignorance) and being brave are two different things [Plato] |
12113 | The search for first or final causes is futile [Comte] |
12110 | We can never know origins, purposes or inner natures [Comte] |