Of moral purpose I see no trace in Nature. That is an article of exclusively human manufacture and very much to our credit.
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.
Proclaim human equality as loudly as you like, Witless will serve his brother.
Science and literature are not two things, but two sides of one thing.
Nothing can be more incorrect than the assumption one sometimes meets with, that physics has one method, chemistry another, and biology a third.
I do not say think as I think, but think in my way. Fear no shadows, least of all in that great spectre of personal unhappiness which binds half the world to orthodoxy.
Science commits suicide when it adopts a creed.
Economy does not lie in sparing money, but in spending it wisely.
Ecclesiasticism in science is only unfaithfulness to truth.
Every great advance in natural knowledge has involved the absolute rejection of authority.
Freedom and order are not incompatible... truth is strength... free discussion is the very life of truth.
History warns us that it is the customary fate of new truths to begin as heresies and to end as superstitions.
If a little knowledge is dangerous, where is the man who has so much as to be out of danger?
I believe that history might be, and ought to be, taught in a new fashion so as to make the meaning of it as a process of evolution intelligible to the young.
It is because the body is a machine that education is possible. Education is the formation of habits, a superinducing of an artificial organization upon the natural organization of the body.