20 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] |
| 10751 | Second-order logic needs the sets, and its consequence has epistemological problems [Rossberg] |
| 10757 | Henkin semantics has a second domain of predicates and relations (in upper case) [Rossberg] |
| 10759 | There are at least seven possible systems of semantics for second-order logic [Rossberg] |
| 10753 | Logical consequence is intuitively semantic, and captured by model theory [Rossberg] |
| 10752 | Γ |- S says S can be deduced from Γ; Γ |= S says a good model for Γ makes S true [Rossberg] |
| 10754 | In proof-theory, logical form is shown by the logical constants [Rossberg] |
| 10756 | A model is a domain, and an interpretation assigning objects, predicates, relations etc. [Rossberg] |
| 10758 | If models of a mathematical theory are all isomorphic, it is 'categorical', with essentially one model [Rossberg] |
| 10761 | Completeness can always be achieved by cunning model-design [Rossberg] |
| 10755 | A deductive system is only incomplete with respect to a formal semantics [Rossberg] |
| 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] |
| 20761 | If existence is absurd it can never have a meaning [Beauvoir] |
| 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] |