14 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] |
14286 | In nearby worlds where A is true, 'if A,B' is true or false if B is true or false [Stalnaker] |
14285 | A possible world is the ontological analogue of hypothetical beliefs [Stalnaker] |
18969 | How do you distinguish three beliefs from four beliefs or two beliefs? [Quine] |
18967 | A 'proposition' is said to be the timeless cognitive part of the meaning of a sentence [Quine] |
18968 | The problem with propositions is their individuation. When do two sentences express one proposition? [Quine] |
18970 | The concept of a 'point' makes no sense without the idea of absolute position [Quine] |