Pierre-Joseph Proudhon is often considered the spiritual godfather of today's radicals. He championed individual liberty and criticized contemporary ideas of private property.
This work, building on another work entitled
What Is Property?, and published posthumously by Proudhon's colleagues, describes Proudhon's view on property in detail. It clearly delineates between private property and personal property and describes to what extent Proudhon believes individuals can restrict access to others in a free society.