23 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] |
19451 | When absorbed in deep reflection, is your reason in control, or is it you? [Feuerbach] |
20416 | By 1790 aestheticians were mainly trying to explain individual artistic genius [Kemp] |
20417 | Expression can be either necessary for art, or sufficient for art (or even both) [Kemp] |
20419 | We don't already know what to express, and then seek means of expressing it [Kemp] |
20418 | The horror expressed in some works of art could equallly be expressed by other means [Kemp] |
19450 | Reason, love and will are the highest perfections and essence of man - the purpose of his life [Feuerbach] |
19448 | Consciousness is said to distinguish man from animals - consciousness of his own species [Feuerbach] |
19454 | A God needs justice, kindness and wisdom, but those concepts don't depend on the concept of God [Feuerbach] |
19452 | The nature of God is an expression of human nature [Feuerbach] |
19453 | If love, goodness and personality are human, the God who is their source is anthropomorphic [Feuerbach] |
19449 | Religion is the consciousness of the infinite [Feuerbach] |
19455 | Today's atheism will tomorrow become a religion [Feuerbach] |