Perhaps as important is the relation between the existence of solutions to a competitive equilibrium and the problems of normative or welfare economics.

可持续发展不是目的地，而是需要持续改进和创新的旅程。

历史不是发生了什么，而是在沉船中幸存下来的东西。

归根结底，哲学是理论领域的阶级斗争。