数学不是一项观赏性运动。你必须亲自去做才能理解它。
Mathematics is not a spectator sport. You have to do it to understand it.
If my world were to cave in tomorrow, I would look back on all the pleasures, excitements and worthwhilenesses I have been lucky enough to have had. Not the sadness, not my miscarriages or my father leaving home, but the joy of everything else. It will have been enough.
The most reliable way to forecast the future is to understand the present.
粮食是百姓生存的根本,没有粮食人就无法生存。三天不吃粮食,父子之间也难以互相照顾。