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

Unity of plan everywhere lies hidden under the mask: of diversity of structure-the complex is everywhere evolved out of the simple.

The student of Nature wonders the more and is astonished the less, the more conversant he becomes with her operations; but of all the perennial miracles she offers to his inspection, perhaps the most worthy of admiration is the development of a plant or of an animal from its embryo.

Size is not grandeur, and territory does not make a nation.

I would rather be the offspring of two apes than be a man and afraid to face the truth.

The struggle for existence holds as much in the intellectual as in the physical world. A theory is a species of thinking, and its right to exist is coextensive with its power of resisting extinction by its rivals.

Science and literature are not two things, but two sides of one thing.