12 ideas
17832 | Zermelo showed that the ZF axioms in 1930 were non-categorical [Zermelo, by Hallett,M] |
13028 | Replacement was added when some advanced theorems seemed to need it [Zermelo, by Maddy] |
18755 | Validity is explained as truth in all models, because that relies on the logical terms [McGee] |
18751 | Natural language includes connectives like 'because' which are not truth-functional [McGee] |
18761 | Second-order variables need to range over more than collections of first-order objects [McGee] |
18753 | An ontologically secure semantics for predicate calculus relies on sets [McGee] |
18754 | Logically valid sentences are analytic truths which are just true because of their logical words [McGee] |
18757 | Soundness theorems are uninformative, because they rely on soundness in their proofs [McGee] |
17626 | The antinomy of endless advance and of completion is resolved in well-ordered transfinite numbers [Zermelo] |
18760 | The culmination of Euclidean geometry was axioms that made all models isomorphic [McGee] |
14296 | Dispositions are physical states of mechanism; when known, these replace the old disposition term [Quine] |
18762 | A maxim claims that if we are allowed to assert a sentence, that means it must be true [McGee] |