17 ideas
13838 | A decent modern definition should always imply a semantics [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] |
13833 | 'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [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] |
12741 | If experience is just a dream, it is still real enough if critical reason is never deceived [Leibniz] |
12740 | The strongest criterion that phenomena show reality is success in prediction [Leibniz] |
12721 | Light, heat and colour are apparent qualities, and so are motion, figure and extension [Leibniz] |
20575 | Socialist economics needs a very strong central power, virtually leading to slavery [Hayek, by Oksala] |
22599 | Hayek was a liberal, but mainly concerned with market freedom [Hayek, by Dunt] |
22600 | Impeding the market is likely to lead to extensive state control [Hayek] |