Mathematics is not a spectator sport.
在你的生活中,有几个地方,或者可能只有一个地方,发生了某件事,然后还有其他所有地方。
The world is not a problem to be solved; it is a living being to which we belong.
激发生命,让生命自由发展,这是教育者的首要任务。
The only way to avoid being miserable is not to have enough leisure to wonder whether you are happy or not.