The secret of joy in work is contained in one word – excellence. To know how to do something well is to enjoy it.

The only way to change behavior is through manipulation of reinforcement contingencies.

好的文学总是留下问题，从不给出绝对的答案。

未来最成功的社会将是那些能够将市场的效率和技术活力与国家提供的社会安全网和政治稳定结合起来的社会。