12 ideas
17879 | Axiomatising set theory makes it all relative [Skolem] |
13536 | Skolem did not believe in the existence of uncountable sets [Skolem] |
17878 | If a 1st-order proposition is satisfied, it is satisfied in a denumerably infinite domain [Skolem] |
17818 | How many? must first partition an aggregate into sets, and then logic fixes its number [Yourgrau] |
17822 | Nothing is 'intrinsically' numbered [Yourgrau] |
17880 | Integers and induction are clear as foundations, but set-theory axioms certainly aren't [Skolem] |
17817 | Defining 'three' as the principle of collection or property of threes explains set theory definitions [Yourgrau] |
17815 | We can't use sets as foundations for mathematics if we must await results from the upper reaches [Yourgrau] |
17821 | You can ask all sorts of numerical questions about any one given set [Yourgrau] |
17881 | Mathematician want performable operations, not propositions about objects [Skolem] |
13165 | Geometrical proofs do not show causes, as when we prove a triangle contains two right angles [Proclus] |
9569 | The origin of geometry started in sensation, then moved to calculation, and then to reason [Proclus] |