学习数学的唯一方法就是做数学。
电影的美在于它让我们能够通过别人的眼睛看世界。
The greatest obstacle to being heroic is the doubt whether one may not be going to prove one's self a fool; the truest heroism is to resist the doubt, and the profoundest wisdom to know when it ought to be resisted, and when it be obeyed.