用心体会整理才能理解精确得当，所以应当沉着稳重，不然就成了口头耳边的小事，过后就忘了。事理要以典故为依据，因此必须学识广博，否则就成了随意推测，胡编乱造。

The mathematician does not study pure mathematics because it is useful; he studies it because he delights in it and he delights in it because it is beautiful.

The soil remembers what we forget: respect it, and it will repay generations.

The value or worth of a man is, as of all other things, his price; that is to say, so much as would be given for the use of his power.

艺术家必须是不可见之物的仆人。