As we know
正如我们所知的那样
There are known knowns
世界上存在有已知的认识
There are things we know we know
有些东西我们知道我们可以理解得了
We also know
我们也知道
There are known unknowns
世界上有人们已承认无法理解的事物
That is to say
也就是说
We know there are some things we don't know
我们承认有些东西我们根本无法理解
But there are unknown unknowns
但也有一些我们不知道的未知事物
The ones we don't know
这种事物我们一无所知
We don't know
我们确实不知道