23 ideas
10688 | 'Equivocation' is when terms do not mean the same thing in premises and conclusion [Beall/Restall] |
10928 | Maybe we can quantify modally if the objects are intensional, but it seems unlikely [Quine] |
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] |
10925 | Failure of substitutivity shows that a personal name is not purely referential [Quine] |
10926 | Quantifying into referentially opaque contexts often produces nonsense [Quine] |
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] |
10930 | Quantification into modal contexts requires objects to have an essence [Quine] |
14645 | To be necessarily greater than 7 is not a trait of 7, but depends on how 7 is referred to [Quine] |
9201 | Whether 9 is necessarily greater than 7 depends on how '9' is described [Quine, by Fine,K] |
10927 | Necessity only applies to objects if they are distinctively specified [Quine] |
9203 | We can't quantify in modal contexts, because the modality depends on descriptions, not objects [Quine, by Fine,K] |
411 | If we succeed in speaking the truth, we cannot know we have done it [Xenophanes] |
412 | If God had not created honey, men would say figs are sweeter [Xenophanes] |
1640 | The basic Eleatic belief was that all things are one [Xenophanes, by Plato] |
10931 | We can't say 'necessarily if x is in water then x dissolves' if we can't quantify modally [Quine] |
3055 | Xenophanes said the essence of God was spherical and utterly inhuman [Xenophanes, by Diog. Laertius] |
407 | Mortals believe gods are born, and have voices and clothes just like mortals [Xenophanes] |
408 | Ethiopian gods have black hair, and Thracian gods have red hair [Xenophanes] |