11 ideas
| 15527 | Defining terms either enables elimination, or shows that they don't require elimination [Lewis] |
| 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] |
| 15530 | A logically determinate name names the same thing in every possible world [Lewis] |
| 1556 | By nature people are close to one another, but culture drives them apart [Hippias] |
| 15531 | The Ramsey sentence of a theory says that it has at least one realisation [Lewis] |
| 15528 | A Ramsey sentence just asserts that a theory can be realised, without saying by what [Lewis] |
| 15526 | There is a method for defining new scientific terms just using the terms we already understand [Lewis] |
| 15529 | It is better to have one realisation of a theory than many - but it may not always be possible [Lewis] |