Anarchism is an anti-authoritarian political philosophy that rejects hierarchies deemed unjust and advocates their replacement with self-managed, self-governed societies based on voluntary, cooperative institutions. These institutions are often described as stateless societies, although several authors have defined them more specifically as distinct institutions based on non-hierarchical or free associations.Pyotr Alexeyevich Kropotkin (December 9, 1842 – February 8, 1921) was a Russian activist, revolutionary, scientist, geographer and philosopher who advocated anarcho-communism.