6 ideas
| 21552 | Common speech is vague; its vocabulary and syntax must be modified, for precision [Russell] |
| 21551 | Empirical words need ostensive definition, which makes them egocentric [Russell] |
| 13127 | Categories can't overlap; they are either disjoint, or inclusive [Sommers, by Westerhoff] |
| 21550 | Science reduces indexicals to a minimum, but they can never be eliminated from empirical matters [Russell] |
| 13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
| 20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |