In the world of letters, learning and knowledge are one, and books are the source of both; whereas in science, as in life, learning and knowledge are distinct, and the study of things, and not of books, is the source of the latter.

The method of scientific investigation is nothing but the expression of the necessary mode of working of the human mind.

Science commits suicide when it adopts a creed.

Ecclesiasticism in science is only unfaithfulness to truth

Genius as an explosive power beats gunpowder hollow; and if knowledge, which should give that power guidance, is wanting, the chances are not small that the rocket will simply run amuck among friends and foes.

I take it that the good of mankind means the attainment, by every man, of all the happiness which he can enjoy without diminishing the happiness of his fellow men

Whatever evil voices may rage, Science, secure among the powers that are eternal, will do her work and be blessed.