17 ideas
| 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] |
| 16066 | Additional or removal of any part changes a thing, so people are never the same person [Epicharmus] |
| 436 | A dog seems handsome to another a dog, and even a pig to another pig [Epicharmus] |
| 20921 | How can we state relativism of sweet and sour, if they have no determinate nature? [Theophrastus] |
| 442 | Pleasures are like pirates - if you are caught they drown you in a sea of pleasures [Epicharmus] |
| 440 | Hands wash hands; give that you may get [Epicharmus] |
| 441 | Against a villain, villainy is not a useless weapon [Epicharmus] |
| 5990 | Theophrastus doubted whether nature could be explained teleologically [Theophrastus, by Gottschalk] |
| 439 | God knows everything, and nothing is impossible for him [Epicharmus] |
| 443 | Human logos is an aspect of divine logos, and is sufficient for successful living [Epicharmus] |