18 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] |
| 2975 | That honey is sweet I do not affirm, but I agree that it appears so [Timon] |
| 7127 | If men are good you should keep promises, but they aren't, so you needn't [Machiavelli] |
| 6309 | The principle foundations of all states are good laws and good armies [Machiavelli] |
| 6306 | People are vengeful, so be generous to them, or destroy them [Machiavelli] |
| 6305 | To retain a conquered state, wipe out the ruling family, and preserve everything else [Machiavelli] |
| 6308 | A sensible conqueror does all his harmful deeds immediately, because people soon forget [Machiavelli] |
| 6307 | A desire to conquer, and men who do it, are always praised, or not blamed [Machiavelli] |
| 7486 | Machiavelli emancipated politics from religion [Machiavelli, by Watson] |
| 19813 | All legislators invoke God in support of extraordinary laws, because their justification is not obvious [Machiavelli] |
| 7126 | Rulers should preserve the foundations of religion, to ensure good behaviour and unity [Machiavelli] |