20 ideas
19259 | If 2-D conceivability can a priori show possibilities, this is a defence of conceptual analysis [Vaidya] |
13838 | A decent modern definition should always imply a semantics [Hacking] |
13833 | 'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking] |
13834 | Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking] |
13835 | Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking] |
13845 | The various logics are abstractions made from terms like 'if...then' in English [Hacking] |
13840 | First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking] |
13844 | A limitation of first-order logic is that it cannot handle branching quantifiers [Hacking] |
13842 | Second-order completeness seems to need intensional entities and possible worlds [Hacking] |
13837 | With a pure notion of truth and consequence, the meanings of connectives are fixed syntactically [Hacking] |
13839 | Perhaps variables could be dispensed with, by arrows joining places in the scope of quantifiers [Hacking] |
13843 | If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking] |
19262 | Essential properties are necessary, but necessary properties may not be essential [Vaidya] |
19267 | Define conceivable; how reliable is it; does inconceivability help; and what type of possibility results? [Vaidya] |
19268 | Inconceivability (implying impossibility) may be failure to conceive, or incoherence [Vaidya] |
19265 | Can you possess objective understanding without realising it? [Vaidya] |
9155 | An a priori proof is independent of experience [Leibniz] |
19260 | Gettier deductive justifications split the justification from the truthmaker [Vaidya] |
19266 | In a disjunctive case, the justification comes from one side, and the truth from the other [Vaidya] |
19264 | Aboutness is always intended, and cannot be accidental [Vaidya] |