What is Property?: An Inquiry into the principle of right and government

P.J. Proudhon was a French politician, mutualist philosopher and socialist. He was a member of the French Parliament, and he was the first person to call himself an "anarchist". He is considered among the most influential theorists and organizers of anarchism. His best know assertion that "Property is theft!" is found in his work What is Property published in 1840 which attracted the attention of the French people of the time.