“But he won’t gain anything by it.” Well, no, I don’t suppose he could get four-and-sixpence a day for being hung, take the year round; but then he stands a chance to save a considerable part of his soul, — and such a soul! — when you do not. No doubt you can get more in your market for a quart of milk than for a quart of blood, but that is not the market that heroes carry their blood to.

Henry David Thoreau (1817-1862) American philosopher and writer

Speech (1859-10-30), “A Plea for Captain John Brown,” Concord, Massachusetts
    (Source)

Speaking of John Brown and his raid on Harpers Ferry. Collected in A Yankee in Canada (1866).