25 ideas
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] |
18253 | I wish to go straight from cardinals to reals (as ratios), leaving out the rationals [Frege] |
18166 | The loss of my Rule V seems to make foundations for arithmetic impossible [Frege] |
22227 | For Sartre there is only being for-itself, or being in-itself (which is beyond experience) [Sartre, by Daigle] |
18269 | Logical objects are extensions of concepts, or ranges of values of functions [Frege] |
20743 | Appearances do not hide the essence; appearances are the essence [Sartre] |
6151 | Sartre says consciousness is just directedness towards external objects [Sartre, by Rowlands] |
6164 | Sartre rejects mental content, and the idea that the mind has hidden inner features [Sartre, by Rowlands] |
7074 | Man is a useless passion [Sartre] |
6687 | Man is the desire to be God [Sartre] |
22228 | Sartre's freedom is not for whimsical action, but taking responsibility for our own values [Sartre, by Daigle] |
22233 | Love is the demand to be loved [Sartre] |
20755 | Fear concerns the world, but 'anguish' comes from confronting my self [Sartre] |
20760 | Sincerity is not authenticity, because it only commits to one particular identity [Sartre, by Aho] |
22231 | We flee from the anguish of freedom by seeing ourselves objectively, as determined [Sartre] |