And the cost of a thing it will be remembered as the amount of life it requires to be exchanged for it. - Henry David Thoreau

The price of anything is the amount of life you exchange for it.

... this hunting of the moose merely for the satisfaction of killing him, —not even for the sake of his hide, —without making any exertion or running any risk yourself, is too much like going out by night to some wood-side pasture and shooting your neighbor's horses.

A man's interest in a single bluebird is worth more than a complete but dry list of the fauna and flora of a town.

Friends — They are like air bubbles on water, hastening to flow together. History tells of Orestes and Pylades, Damon and Pythias, but why should not we put to shame those old reserved worthies by a community of such? Constantly, as it were through a remote skylight, I have glimpses of a serene friendship-land, and know the better why brooks murmur and violets grow. This conjunction of souls, like waves which met and break, subsides also backward over things, and gives all a fresh aspect. I would live henceforth with some gentle soul such a life as may be conceived, double for variety, single for harmony — two, only that we might admire at our oneness — one, because indivisible. Such community to be a pledge of holy living. How could aught unworthy be admitted into our society? To listen with one ear to each summer sound, to behold with one eye each summer scene, our visual rays so to meet and mingle with the object as to be one bent and doubled; with two tongues to be wearied, and thought to spring ceaselessly from a double fountain.