The science of life is a superb and dazzlingly lighted hall which may be reached only by passing through a long and ghastly kitchen.

Priestley [said] that each discovery we make shows us many others that should be made.

Science does not permit exceptions.

It is what we know already that often prevents us from learning.

We must keep our freedom of mind, ... and must believe that in nature what is absurd, according to our theories, is not always impossible.

We achieve more than we know. We know more than we understand. We understand more than we can explain.

A man of science rises ever, in seeking truth; and if he never finds it in its wholeness, he discovers nevertheless very significant fragments; and these fragments of universal truth are precisely what constitutes science.