15 ideas
| 10688 | 'Equivocation' is when terms do not mean the same thing in premises and conclusion [Beall/Restall] |
| 10690 | Formal logic is invariant under permutations, or devoid of content, or gives the norms for thought [Beall/Restall] |
| 10691 | Logical consequence needs either proofs, or absence of counterexamples [Beall/Restall] |
| 10695 | Logical consequence is either necessary truth preservation, or preservation based on interpretation [Beall/Restall] |
| 10689 | A step is a 'material consequence' if we need contents as well as form [Beall/Restall] |
| 10696 | A 'logical truth' (or 'tautology', or 'theorem') follows from empty premises [Beall/Restall] |
| 10693 | Models are mathematical structures which interpret the non-logical primitives [Beall/Restall] |
| 10692 | Hilbert proofs have simple rules and complex axioms, and natural deduction is the opposite [Beall/Restall] |
| 4304 | Descartes says there are two substance, Spinoza one, and Leibniz infinitely many [Cottingham] |
| 17368 | Essentialism concerns the nature of a group, not its category [Devitt] |
| 17370 | Things that gradually change, like species, can still have essences [Devitt] |
| 4303 | The notion of substance lies at the heart of rationalist metaphysics [Cottingham] |
| 4306 | For rationalists, it is necessary that effects be deducible from their causes [Cottingham] |
| 17369 | We name species as small to share properties, but large enough to yield generalisations [Devitt] |
| 17367 | Species are phenetic, biological, niche, or phylogenetic-cladistic [Devitt, by PG] |