It is not that we love to be alone, but that we love to soar, and when we do soar, the company grows thinner and thinner until there is none at all. …We are not the less to aim at the summits though the multitude does not ascend them.

What fire could ever equal the sunshine of a winter's day?

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.

The mass of men lead lives of quiet desperation.

I think we may safely trust a good deal more than we do.

How can you expect the birds to sing when their groves are cut down?

The authority of government . . . can have no pure right over my person and property but what I concede to it.