Surely there is a time to submit to guidance and a time to take one's own way at all hazards.

Agnosticism simply means that a man shall not say that he knows or believes that for which he has no grounds for professing to believe.

All knowledge is good. It is impossible to say any fragment of knowledge, however insignificant or remote from one's ordinary pursuits, may not some day be turned to account.

Life is too short to occupy oneself with the slaying of the slain more than once.

It is the first duty of a hypothesis to be intelligible.

I cannot but think that he who finds a certain proportion of pain and evil inseparably woven up in the life of the very worms, will bear his own share with more courage and submission.

Nothing great in science has ever been done by men, whatever their powers, in whom the divine afflatus of the truth-seeker was wanting.