Psychology must be a purely descriptive science.

The true revolutionary is guided by a great feeling of love. It is impossible to think of a genuine revolutionary lacking this quality.

Purposive behavior in animals and men.

我总是努力寻找解决办法，而不是借口。

"Poetry is the establishment of being by means of the word."

只有掌握核心技术，才能立于不败之地。