世间万物，没有孤立存在的，必然有其对立面。
心理学唯一有效的数据是可观察的行为。
The improvement of the productive powers of labor, and the greater part of the skill, dexterity, and judgement with which it is anywhere directed or applied, seem to have been the effects of division of labor.
I do not want to be a star. I do not think that the way I live is something that should be imitated.
我不想成为明星。我不认为我的生活方式是应该被模仿的。
最好的投资策略是坚持有纪律的长期方法。
幸运所需要的美德是节制，逆境所需要的美德是坚韧。