A problem that can be solved with money is not really a problem.
This was a very short visit, but it plunged the little prince into deep dejection.
预测未来的最好方法就是创造未来。
被视为行为系统的人类其实相当简单。我们行为表面上的复杂性很大程度上反映了我们所处环境的复杂性。