If the injustice is part of the necessary friction of the machine of government, let it go, let it go: perchance it will wear smooth,—certainly the machine will wear out. If the injustice has a spring, or a pulley, or a rope, or a crank, exclusively for itself, then perhaps you may consider whether the remedy will not be worse than the evil; but if it is of such a nature that it requires you to be the agent of injustice to another, then, I say, break the law. Let your life be a counter- friction to stop the machine. What I have to do is to see, at any rate, that I do not lend myself to the wrong which I condemn.
-Henry David Thoreau, “Civil Disobedience,” originally published as “Resistance to Civil Government” (1849), in The Writings of Henry David Thoreau, vol. 4, p. 368, Houghton Mifflin (1906)