Clarence Lee Swartz was an American individualist anarchist, whose best-known work, What is Mutualism? is a book explaining the economic system of mutualism.
Individualist anarchism in the United States was strongly influenced by Benjamin Tucker, Josiah Warren, Ralph Waldo Emerson, Lysander Spooner, Pierre-Joseph Proudhon, Max Stirner, Herbert Spencer and
What Is Property? (1840) by Pierre-Joseph Proudhon