But if [the machine of government] 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.

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.