16 ideas
8378 | Philosophers usually learn science from each other, not from science [Russell] |
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] |
8375 | 'Necessary' is a predicate of a propositional function, saying it is true for all values of its argument [Russell] |
18555 | The beautiful is that from which nothing can be subtracted and to which nothing can be added [Alberti] |
4396 | The law of causality is a source of confusion, and should be dropped from philosophy [Russell] |
8376 | If causes are contiguous with events, only the last bit is relevant, or the event's timing is baffling [Russell] |
8380 | Striking a match causes its igniting, even if it sometimes doesn't work [Russell] |
8379 | In causal laws, 'events' must recur, so they have to be universals, not particulars [Russell] |
8381 | The constancy of scientific laws rests on differential equations, not on cause and effect [Russell] |