19 ideas
| 16123 | Whenever you perceive a community of things, you should also hunt out differences in the group [Plato] |
| 16125 | To reveal a nature, divide down, and strip away what it has in common with other things [Plato] |
| 16124 | No one wants to define 'weaving' just for the sake of weaving [Plato] |
| 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] |
| 5961 | The soul gets its goodness from god, and its evil from previous existence. [Plato] |
| 283 | The question of whether or not to persuade comes before the science of persuasion [Plato] |
| 282 | Non-physical beauty can only be shown clearly by speech [Plato] |
| 281 | The arts produce good and beautiful things by preserving the mean [Plato] |
| 22559 | Democracy is the worst of good constitutions, but the best of bad constitutions [Plato, by Aristotle] |
| 279 | Only divine things can always stay the same, and bodies are not like that [Plato] |
| 16713 | Philosophers are the forefathers of heretics [Tertullian] |
| 6610 | I believe because it is absurd [Tertullian] |