一切人类知识都源于经验。

译文：古代的士、农、工、商四种职业不同但遵循的道是相同的，他们尽自己的心力，在这一点上是一样的。

The world is a place of the living, and the dead have no place in it. The dead are nothing. They are not even a memory. They are forgotten. And the living, too, will be forgotten.