正是这种理解力使人凌驾于其他所有动物之上，并使人能够利用和支配它们，
因此，我们当然值得花时间去研究它。
Since it is the understanding that sets man above all other animals and enables him to use and dominate them,
it is certainly worth our while to enquire into it.
当我们对考虑的事物没有确切的知识时，
应该用什么样的规则或标准来指导我们，使我们相信我们的观点是正确的？
When we are concerned with something about which we have no certain knowledge,
what rules or standards should guide how confident we allow ourselves to be that our opinions are right?
我希望这种对理解力的本质的探究能使我发现它的力量有多大，
它能达到什么程度，它能处理什么事情，以及它在什么地方不能满足我们。
如果我成功了，这可能会说服人类忙碌的头脑在干涉超出其理解能力的事情时更加谨慎;
当它处于极限时停止;
对我们能力所及之外的事情，要坦然接受无知。
I hope that this enquiry into the nature of the understanding will enable me to discover what its powers are
how far they reach, what things they are adequate to deal with, and where they fail us.
If I succeed, that may have the effect of persuading the busy mind of man to be more cautious in meddling with things that are beyond its powers to understand;
to stop when it is at the extreme end of its tether;
and to be peacefully reconciled to ignorance of things that turn out to be beyond the reach of our capacities.
摘自 Chapter i: Introductio