It is so easy to hide our ignorance under such expressions as the plan of creation or unity of design, etc., and to think that we give an explanation when we only restate a fact.

Ignorance more frequently begets confidence than does knowledge: it is those who know little, and not those who know much, who so positively assert that this or that problem will never be solved by science.

It is always advisable to perceive clearly our ignorance.

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

Beware of false knowledge; it is more dangerous than ignorance.

To Believe without evidence and demonstration is an act of ignorance and folly.