数学中最深刻的问题往往源于最简单的问题。
The deepest problems in mathematics often arise from the simplest questions.
贫贱时,对富贵漠然置之,他日得志一定不自矜;富贵之时,心中不忘贫贱之日,即便失却富贵心中也必无怪怨。
"History is not the past—it is the method we have evolved of organizing our ignorance of the past."