20 ideas
16415 | Esoteric metaphysics aims to be top science, investigating ultimate reality [Hofweber] |
16413 | Science has discovered properties of things, so there are properties - so who needs metaphysics? [Hofweber] |
10147 | The Axiom of Choice is consistent with the other axioms of set theory [Feferman/Feferman] |
10148 | Axiom of Choice: a set exists which chooses just one element each of any set of sets [Feferman/Feferman] |
10149 | Platonist will accept the Axiom of Choice, but others want criteria of selection or definition [Feferman/Feferman] |
10150 | The Trichotomy Principle is equivalent to the Axiom of Choice [Feferman/Feferman] |
10146 | Cantor's theories needed the Axiom of Choice, but it has led to great controversy [Feferman/Feferman] |
16416 | The quantifier in logic is not like the ordinary English one (which has empty names, non-denoting terms etc) [Hofweber] |
10158 | A structure is a 'model' when the axioms are true. So which of the structures are models? [Feferman/Feferman] |
10162 | Tarski and Vaught established the equivalence relations between first-order structures [Feferman/Feferman] |
10160 | Löwenheim-Skolem says if the sentences are countable, so is the model [Feferman/Feferman] |
10159 | Löwenheim-Skolem Theorem, and Gödel's completeness of first-order logic, the earliest model theory [Feferman/Feferman] |
10161 | If a sentence holds in every model of a theory, then it is logically derivable from the theory [Feferman/Feferman] |
10156 | 'Recursion theory' concerns what can be solved by computing machines [Feferman/Feferman] |
10155 | Both Principia Mathematica and Peano Arithmetic are undecidable [Feferman/Feferman] |
18228 | An end can't be an ultimate value just because it is useless! [Korsgaard] |
18225 | If we can't reason about value, we can reason about the unconditional source of value [Korsgaard] |
18224 | Goodness is given either by a psychological state, or the attribution of a property [Korsgaard] |
18233 | Contemplation is final because it is an activity which is not a process [Korsgaard] |
18226 | For Aristotle, contemplation consists purely of understanding [Korsgaard] |