29 ideas
15970 | People generalise because it is easier to understand, and that is mistaken for deep philosophy [Feynman] |
13838 | A decent modern definition should always imply a semantics [Hacking] |
14273 | Conditional Proof is only valid if we accept the truth-functional reading of 'if' [Edgington] |
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] |
14281 | A thing works like formal probability if all the options sum to 100% [Edgington] |
14284 | Conclusion improbability can't exceed summed premise improbability in valid arguments [Edgington] |
14270 | Simple indicatives about past, present or future do seem to form a single semantic kind [Edgington] |
14269 | Maybe forward-looking indicatives are best classed with the subjunctives [Edgington] |
14275 | Truth-function problems don't show up in mathematics [Edgington] |
14274 | Inferring conditionals from disjunctions or negated conjunctions gives support to truth-functionalism [Edgington] |
14276 | The truth-functional view makes conditionals with unlikely antecedents likely to be true [Edgington] |
14290 | Doctor:'If patient still alive, change dressing'; Nurse:'Either dead patient, or change dressing'; kills patient! [Edgington] |
14271 | Non-truth-functionalist say 'If A,B' is false if A is T and B is F, but deny that is always true for TT,FT and FF [Edgington] |
14272 | I say "If you touch that wire you'll get a shock"; you don't touch it. How can that make the conditional true? [Edgington] |
14282 | On the supposition view, believe if A,B to the extent that A&B is nearly as likely as A [Edgington] |
14278 | Truth-functionalists support some conditionals which we assert, but should not actually believe [Edgington] |
14287 | Does 'If A,B' say something different in each context, because of the possibiites there? [Edgington] |
9410 | Physical Laws are rhythms and patterns in nature, revealed by analysis [Feynman] |
18530 | Nobody understands quantum mechanics [Feynman] |
17707 | We should regard space as made up of many tiny pieces [Feynman, by Mares] |