We do not protect freedom in order to indulge error. We protect freedom in order to discover truth. We do not maintain freedom in order to permit eccentricity to flourish; we maintain freedom in order that society may profit from criticism, even eccentric criticism. We do not encourage dissent for sentimental reasons; we encourage dissent because we cannot live without it.

Henry Steele Commager (1902-1998) American historian, writer, activist

“The Necessity of Freedom,” Freedom, Loyalty, Dissent (1954)
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An earlier version of the essay was given as "The Pragmatic Necessity for Freedom," Cooper Lecture, Swarthmore College (1951).