3 ideas
3299 | In logic identity involves reflexivity (x=x), symmetry (if x=y, then y=x) and transitivity (if x=y and y=z, then x=z) [Baillie] |
16861 | A false theory could hardly rival the explanatory power of natural selection [Darwin] |
5470 | The idea of laws of nature arose in the Middle Ages [Hall,AR, by Ellis] |