11 ideas
17833 | The first-order ZF axiomatisation is highly non-categorical [Hallett,M] |
17834 | Non-categoricity reveals a sort of incompleteness, with sets existing that the axioms don't reveal [Hallett,M] |
17837 | Zermelo allows ur-elements, to enable the widespread application of set-theory [Hallett,M] |
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] |
17836 | The General Continuum Hypothesis and its negation are both consistent with ZF [Hallett,M] |
13345 | Sentences are 'analytical' if every sequence of objects models them [Tarski] |
5049 | Intelligent pleasure is the perception of beauty, order and perfection [Leibniz] |
5048 | Perfection is simply quantity of reality [Leibniz] |
5050 | Evil serves a greater good, and pain is necessary for higher pleasure [Leibniz] |