He is not a true man of science who does not bring some sympathy to his studies, and expect to learn something by behavior as well as by application. It is childish to rest in the discovery of mere coincidences, or of partial and extraneous laws. The study of geometry is a petty and idle exercise of the mind, if it is applied to no larger system than the starry one. Mathematics should be mixed not only with physics but with ethics; that is mixed mathematics. The fact which interests us most is the life of the naturalist. The purest science is still biographical.

From my experience with wild apples, I can understand that there may be reason for a savage's preferring many kinds of food which the civilized man rejects. The former has the palate of an outdoor man. It takes a savage or wild taste to appreciate a wild fruit.

And if the civilized man's pursuits are no worthier than the savage's, if he is employed the greater part of his life in obtaininggross necessaries and comforts merely, why should he have a better dwelling than the former?

New ideas come into this world somewhat like falling meteors, with a flash and an explosion.

When we walk, we naturally go to the fields and woods: what would become of us, if we walked only in a garden or a mall?

I have a deep sympathy with war; it so apes the gait and bearing of the soul.

Roads are made for horses and men of business. I do not travel in them much.