Purity of heart is to will one thing.
自己不愿意的，不要强加给别人。
The only way to learn mathematics is to do mathematics.
The energy you put out is the energy you get back.
优良的马匹不好驾驭，但是可以载重物跑得很远；有才能的人不好驱使，但是可以使国君更加受人尊敬。