4 ideas
18189 | ZFC could contain a contradiction, and it can never prove its own consistency [MacLane] |
8638 | Thomae's idea of abstract from peculiarities gives a general concept, and leaves the peculiarities [Frege on Thomae] |
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] |