Life consists in penetrating the unknown, and fashioning our actions in accord with the new knowledge thus acquired.

True knowledge exists in knowing that you know nothing.

Never be afraid of not knowing. Find out.

It is true that impatience, the mother of stupidity, praises brevity, as if such persons had not life long enough to serve them to acquire a complete knowledge of one single subject, such as the human body; and then they want to comprehend the mind of God in which the universe is included, weighing it minutely and mincing it into infinite parts, as if they had to dissect it!

Where there is shouting, there is no true knowledge.

All our knowledge has its origins in our perceptions.