12 ideas
10688 | 'Equivocation' is when terms do not mean the same thing in premises and conclusion [Beall/Restall] |
15102 | S4 says there must be some necessary truths (the actual ones, of which there is at least one) [Cameron] |
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] |
15103 | Blackburn fails to show that the necessary cannot be grounded in the contingent [Cameron] |
15104 | The 'moving spotlight' theory makes one time privileged, while all times are on a par ontologically [Cameron] |
16689 | The schools said spirits lack extension, and wonder how many could dance on a needle's point [More,H] |