Our true mentor in life is science.

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.

Thoroughly conscious ignorance is the prelude to every real advance in science.

Wrongly do men cry out against experience and with bitter re- proaches accuse her of deceitfulness. Let experience alone, and rather turn your complaints against your own ignorance, which causes you to be so carried away by your vain and insensate desires as to expect from experience things which are not within her power!

Nothing is easier than to admit in words the truth of the universal struggle for life, or more difficult, at least I have found it so, than constantly to bear this conclusion in mind.

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.