A liberal society stands on the proposition that we should all take seriously the idea that we might be wrong. This means we must place no one, including ourselves, beyond the reach of criticism; it means that we must allow people to err, even where the error offends and upsets, as it often will.

Kindly Inquisitors: The New Attacks on Free Thought, Expanded Edition (ed. University of Chicago Press, 2013) - ISBN: 9780226130552