Lysander Spooner

Spooner was a strong advocate of the labor movement and is politically identified with individualist anarchism. His writings contributed to the development of both left-libertarian and right-libertarian political theory. Spooner's writings include the abolitionist book ''The Unconstitutionality of Slavery'' and ''No Treason: The Constitution of No Authority,'' which opposed treason charges against secessionists.
He is known for establishing the American Letter Mail Company, which competed with the United States Postal Service. Provided by Wikipedia