15 ideas
| 20350 | Metaphysics generalises the data, to get at the ontology [Richardson] |
| 20349 | Metaphysics aims at the essence of things, and a system to show how this explains other truths [Richardson] |
| 20351 | Metaphysics needs systems, because analysis just obsesses over details [Richardson] |
| 13913 | The four 'perfect syllogisms' are called Barbara, Celarent, Darii and Ferio [Engelbretsen/Sayward] |
| 13914 | Syllogistic logic has one rule: what is affirmed/denied of wholes is affirmed/denied of their parts [Engelbretsen/Sayward] |
| 13915 | Syllogistic can't handle sentences with singular terms, or relational terms, or compound sentences [Engelbretsen/Sayward] |
| 13916 | Term logic uses expression letters and brackets, and '-' for negative terms, and '+' for compound terms [Engelbretsen/Sayward] |
| 13850 | In modern logic all formal validity can be characterised syntactically [Engelbretsen/Sayward] |
| 13849 | Classical logic rests on truth and models, where constructivist logic rests on defence and refutation [Engelbretsen/Sayward] |
| 13851 | Unlike most other signs, = cannot be eliminated [Engelbretsen/Sayward] |
| 13852 | Axioms are ω-incomplete if the instances are all derivable, but the universal quantification isn't [Engelbretsen/Sayward] |
| 20356 | Humans dominate because, unlike other animals, they have a synthesis of conflicting drives [Richardson] |
| 13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
| 20366 | A mind that could see cause and effect as a continuum would deny cause and effect [Richardson] |
| 20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |