3 ideas
8920 | Equivalence relations are reflexive, symmetric and transitive, and classify similar objects [Lipschutz] |
10190 | From the axiomatic point of view, mathematics is a storehouse of abstract structures [Bourbaki] |
3031 | The greatest good is not the achievement of desire, but to desire what is proper [Menedemus, by Diog. Laertius] |