20 ideas
5021 | An idea is analysed perfectly when it is shown a priori that it is possible [Leibniz] |
6806 | Do not multiply entities beyond necessity [William of Ockham] |
10301 | The axiom of choice is controversial, but it could be replaced [Shapiro] |
10588 | First-order logic is Complete, and Compact, with the Löwenheim-Skolem Theorems [Shapiro] |
10298 | Some say that second-order logic is mathematics, not logic [Shapiro] |
10299 | If the aim of logic is to codify inferences, second-order logic is useless [Shapiro] |
10300 | Logical consequence can be defined in terms of the logical terminology [Shapiro] |
10290 | Second-order variables also range over properties, sets, relations or functions [Shapiro] |
10590 | Up Löwenheim-Skolem: if natural numbers satisfy wffs, then an infinite domain satisfies them [Shapiro] |
10296 | The Löwenheim-Skolem Theorems fail for second-order languages with standard semantics [Shapiro] |
10297 | The Löwenheim-Skolem theorem seems to be a defect of first-order logic [Shapiro] |
10292 | Downward Löwenheim-Skolem: if there's an infinite model, there is a countable model [Shapiro] |
10294 | Second-order logic has the expressive power for mathematics, but an unworkable model theory [Shapiro] |
10591 | Logicians use 'property' and 'set' interchangeably, with little hanging on it [Shapiro] |
22132 | Species and genera are individual concepts which naturally signify many individuals [William of Ockham] |
5020 | Our thoughts are either dependent, or self-evident. All thoughts seem to end in the self-evident [Leibniz] |
5019 | Supreme human happiness is the greatest possible increase of his perfection [Leibniz] |
19381 | The past has ceased to exist, and the future does not yet exist, so time does not exist [William of Ockham] |
8010 | William of Ockham is the main spokesman for God's commands being the source of morality [William of Ockham] |
16679 | Even an angel must have some location [William of Ockham, by Pasnau] |