10 ideas
18812 | Split out the logical vocabulary, make an assignment to the rest. It's logical if premises and conclusion match [Tarski, by Rumfitt] |
13344 | X follows from sentences K iff every model of K also models X [Tarski] |
13343 | A 'model' is a sequence of objects which satisfies a complete set of sentential functions [Tarski] |
23026 | We know mathematical axioms, such as subtracting equals from equals leaves equals, by a natural light [Leibniz] |
13189 | A necessary feature (such as air for humans) is not therefore part of the essence [Leibniz] |
19432 | Intelligible truth is independent of any external things or experiences [Leibniz] |
19430 | We know objects by perceptions, but their qualities don't reveal what it is we are perceiving [Leibniz] |
19431 | There is nothing in the understanding but experiences, plus the understanding itself, and the understander [Leibniz] |
13345 | Sentences are 'analytical' if every sequence of objects models them [Tarski] |
5845 | Niceratus learnt the whole of Homer by heart, as a guide to goodness [Xenophon] |