33 ideas
8092 | Logic was merely a branch of rhetoric until the scientific 17th century [Devlin] |
8081 | 'No councillors are bankers' and 'All bankers are athletes' implies 'Some athletes are not councillors' [Devlin] |
8085 | Modern propositional inference replaces Aristotle's 19 syllogisms with modus ponens [Devlin] |
8086 | Predicate logic retains the axioms of propositional logic [Devlin] |
8091 | Situation theory is logic that takes account of context [Devlin] |
8089 | Montague's intensional logic incorporated the notion of meaning [Devlin] |
8087 | Golden ages: 1900-1960 for pure logic, and 1950-1985 for applied logic [Devlin] |
8082 | Where a conditional is purely formal, an implication implies a link between premise and conclusion [Devlin] |
8072 | Sentences of apparent identical form can have different contextual meanings [Devlin] |
11115 | 'All horses' either picks out the horses, or the things which are horses [Jubien] |
8075 | Space and time are atomic in the arrow, and divisible in the tortoise [Devlin] |
11116 | Being a physical object is our most fundamental category [Jubien] |
11117 | Haecceities implausibly have no qualities [Jubien] |
11119 | De re necessity is just de dicto necessity about object-essences [Jubien] |
11118 | Modal propositions transcend the concrete, but not the actual [Jubien] |
11108 | Your properties, not some other world, decide your possibilities [Jubien] |
11111 | Modal truths are facts about parts of this world, not about remote maximal entities [Jubien] |
11105 | We have no idea how many 'possible worlds' there might be [Jubien] |
11109 | If other worlds exist, then they are scattered parts of the actual world [Jubien] |
11106 | If all possible worlds just happened to include stars, their existence would be necessary [Jubien] |
11107 | If there are no other possible worlds, do we then exist necessarily? [Jubien] |
11112 | Possible worlds just give parallel contingencies, with no explanation at all of necessity [Jubien] |
11113 | Worlds don't explain necessity; we use necessity to decide on possible worlds [Jubien] |
11110 | We mustn't confuse a similar person with the same person [Jubien] |
17771 | How we evaluate evidence depends on our background beliefs [Bayne] |
17770 | Clifford's dictum seems to block our beliefs in morality, politics and philosophy [Bayne] |
8088 | People still say the Hopi have no time concepts, despite Whorf's later denial [Devlin] |
17766 | Physicalism correlates brain and mind, explains causation by thought, and makes nature continuous [Bayne] |
17768 | Perception reveals what animals think, but humans can disengage thought from perception [Bayne] |
17769 | Some people centre space on themselves; others centre space on the earth [Bayne] |
17767 | The alternative to a language of thought is map-like or diagram-like thought [Bayne] |
8073 | How do we parse 'time flies like an arrow' and 'fruit flies like an apple'? [Devlin] |
8076 | The distinction between sentences and abstract propositions is crucial in logic [Devlin] |