A man’s life should be constantly as fresh as this river. It should be the same channel, but a new water every instant…Most men have no inclination, no rapids, no cascades, but marshes, and alligators, and miasma instead.

– Henry David Thoreau, from “Monday,” A Week on the Concord and Merrimack Rivers (location 283-284 of 882)

Longer, with more context:

Undoubtedly, countless reforms are called for, because society is not animated, or instinct enough with life… All men are partially buried in the grave of custom, and of some we see only the crown of the head above ground. Better are the physically dead, for they more lively rot. Even virtue is no longer such if it be stagnant. A man’s life should be constantly as fresh as this river. It should be the same channel, but a new water every instant…Most men have no inclination, no rapids, no cascades, but marshes, and alligators, and miasma instead.

– Henry David Thoreau, from “Monday,” A Week on the Concord and Merrimack Rivers (location 283-284 of 882)