No one had ever had such a friend, so affectionate,so loyal and so skillful.

"To love is to risk not being loved in return. To hope is to risk pain. To try is to risk failure, but risk must be taken because the greatest hazard in life is to risk nothing."

You don't love because: you love despite; not for the virtues, but despite the faults.

减少思虑，来调养心气；减少性欲来调养肾气；不要妄动，来调养骨气；戒止嗔怒，来调养肝气；饮食素淡，来调养胃气；减少话语，来调养神气；博鉴群书，来调养胆气；顺应时令，来调养元气。

每一个数学问题都是一个等待解决的谜题，每一个解决方案都是迈向更深入理解的一步。