40 ideas
8092 | Logic was merely a branch of rhetoric until the scientific 17th century [Devlin] |
21360 | Unobservant thinkers tend to dogmatise using insufficient facts [Aristotle] |
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] |
8087 | Golden ages: 1900-1960 for pure logic, and 1950-1985 for applied logic [Devlin] |
8089 | Montague's intensional logic incorporated the notion of meaning [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] |
8075 | Space and time are atomic in the arrow, and divisible in the tortoise [Devlin] |
13212 | Infinity is only potential, never actual [Aristotle] |
13221 | Existence is either potential or actual [Aristotle] |
16100 | True change is in a thing's logos or its matter, not in its qualities [Aristotle] |
16101 | A change in qualities is mere alteration, not true change [Aristotle] |
12133 | If the substratum persists, it is 'alteration'; if it doesn't, it is 'coming-to-be' or 'passing-away' [Aristotle] |
13213 | All comings-to-be are passings-away, and vice versa [Aristotle] |
12134 | Matter is the substratum, which supports both coming-to-be and alteration [Aristotle] |
16572 | Does the pure 'this' come to be, or the 'this-such', or 'so-great', or 'somewhere'? [Aristotle] |
16573 | Philosophers have worried about coming-to-be from nothing pre-existing [Aristotle] |
13214 | The substratum changing to a contrary is the material cause of coming-to-be [Aristotle] |
13215 | If a perceptible substratum persists, it is 'alteration'; coming-to-be is a complete change [Aristotle] |
16717 | Which of the contrary features of a body are basic to it? [Aristotle] |
8088 | People still say the Hopi have no time concepts, despite Whorf's later denial [Devlin] |
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] |
1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
13216 | Matter is the limit of points and lines, and must always have quality and form [Aristotle] |
17994 | The primary matter is the substratum for the contraries like hot and cold [Aristotle] |
13224 | There couldn't be just one element, which was both water and air at the same time [Aristotle] |
16594 | The Four Elements must change into one another, or else alteration is impossible [Aristotle] |
13223 | Fire is hot and dry; Air is hot and moist; Water is cold and moist; Earth is cold and dry [Aristotle] |
13220 | Bodies are endlessly divisible [Aristotle] |
13210 | Wood is potentially divided through and through, so what is there in the wood besides the division? [Aristotle] |
13211 | If a body is endlessly divided, is it reduced to nothing - then reassembled from nothing? [Aristotle] |
13228 | There is no time without movement [Aristotle] |
16595 | If each thing can cease to be, why hasn't absolutely everything ceased to be long ago? [Aristotle] |
5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |
13227 | Being is better than not-being [Aristotle] |
13226 | An Order controls all things [Aristotle] |