20 ideas
8877 | We can't attain a coherent system by lopping off any beliefs that won't fit [Sosa] |
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] |
8884 | The phenomenal concept of an eleven-dot pattern does not include the concept of eleven [Sosa] |
8878 | It is acceptable to say a supermarket door 'knows' someone is approaching [Sosa] |
8880 | In reducing arithmetic to self-evident logic, logicism is in sympathy with rationalism [Sosa] |
8881 | Most of our knowledge has insufficient sensory support [Sosa] |
8882 | Perception may involve thin indexical concepts, or thicker perceptual concepts [Sosa] |
8883 | Do beliefs only become foundationally justified if we fully attend to features of our experience? [Sosa] |
8885 | Some features of a thought are known directly, but others must be inferred [Sosa] |
8876 | Much propositional knowledge cannot be formulated, as in recognising a face [Sosa] |
8879 | Fully comprehensive beliefs may not be knowledge [Sosa] |
1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |