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It is the duty of the inventor to make his work as useful and as accessible as possible to the public.

數學的語言是普遍的，超越了文化和語言的障礙。

The very shaping of history now outpaces the ability of men to orient themselves in accordance with cherished values. And which values? Even when they do not panic, men often sense that older ways of feeling and thinking have collapsed and that newer beginnings are ambiguous to the point of moral stasis.

The art of teaching is the art of assisting discovery.

Stray birds of summer come to my window to sing and fly away. And yellow leaves of autumn, which have no songs,flutter and fall there with a sigh.

世上還沒有一種方法，可以從一個人的臉上探察他的居心；他是我所曾經絕對信任的一個人。