It is not who is right, but what is right, that is of importance.

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.

The more rapidly truth is spread among mankind the better it will be for them. Only let us be sure that it is the truth.

In matters of the intellect, do not pretend that conclusions are certain which are not demonstrated or demonstrable. That I take to be the agnostic faith, which if a man keep whole and undefiled, he shall not be ashamed to look the universe in the face, whatever the future may have in store for him.

And when you cannot prove that people are wrong, but only that they are absurd, the best course is to let them alone.

Misery is a match that never goes out.

Science has fulfilled her function when she has ascertained and enunciated truth.