An Enquiry Concerning Human Understanding

Propositions of this kind are discoverable by the mere operation of thought, without dependence on what is anywhere existent in the universe.

这类命题仅凭思维活动便可发现，无须依赖宇宙中任何现存之物。

The best expedient to prevent this confusion, is to be modest in our pretensions; and even to discover the difficulty ourselves before it is objected to us.

防止这种混乱的最好办法，就是对我们的主张保持谦逊；甚至在别人提出之前，先自己发现其中的困难。