The essence of knowledge is, having it, to apply it; not having it, to confess your ignorance.

Real knowledge is to know the extent of one's ignorance.

Close beside my knowledge lies my black ignorance.

Some are born with knowledge, some derive it from study, and some acquire it only after a painful realization of their ignorance. But the knowledge being possessed, it comes to the same thing. Some study with a natural ease, some from a desire for advantages, and some by strenuous effort. But the achievement being made, it comes to the same thing.

The only good is knowledge and the only evil is ignorance.

It is the perfection of God's works that they are all done with the greatest simplicity. He is the God of order and not of confusion. And therefore as they would understand the frame of the world must endeavor to reduce their knowledge to all possible simplicity, so must it be in seeking to understand these visions.