The purpose of abstraction is not to be vague, but to create a new semantic level in which one can be absolutely precise.

不忘初心，方得始终，我们要始终牢记"我为祖国献石油"的使命。

Science should serve humanity, not the other way around.

出自汉·桓宽《盐铁论·地广》。释义：不因为生活的贫困而改变自己的节操，不因为地位的低贱而变更自己的志向。