12 ideas
| 23269 | Philosophy must start from clearly observed facts [Galen] |
| 8083 | Boole applied normal algebra to logic, aiming at an algebra of thought [Boole, by Devlin] |
| 7727 | Boole's notation can represent syllogisms and propositional arguments, but not both at once [Boole, by Weiner] |
| 8686 | Boole made logic more mathematical, with algebra, quantifiers and probability [Boole, by Friend] |
| 22277 | Boole's method was axiomatic, achieving economy, plus multiple interpretations [Boole, by Potter] |
| 1556 | By nature people are close to one another, but culture drives them apart [Hippias] |
| 23266 | The spirit in the soul wants freedom, power and honour [Galen] |
| 23219 | Stopping the heart doesn't terminate activity; pressing the brain does that [Galen, by Cobb] |
| 23264 | Philosophers think faculties are in substances, and invent a faculty for every activity [Galen] |
| 23220 | The brain contains memory and reason, and is the source of sensation and decision [Galen] |
| 23265 | The rational part of the soul is the desire for truth, understanding and recollection [Galen] |
| 23268 | We execute irredeemable people, to protect ourselves, as a deterrent, and ending a bad life [Galen] |