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 (1817-1862) American philosopher and writer

Essay (1849-05), “Resistance to Civil Government [On the Duty of Civil Disobedience],” Æsthetic Papers, No. 1, Article 10
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Based on an 1848 lecture at the Concord Lyceum.