Anarchist.
Prince Pyotr Alexeyevich Kropotkin (9 December 1842 – 8 February 1921) was a Russian zoologist, evolutionary theorist, philosopher, scientist, revolutionary, economist, activist, geographer, writer, and one of the world's foremost anarcho-communists.
Kropotkin advocated a communist society free from central government and based on voluntary associations between workers. He wrote many books, pamphlets and articles, the most prominent being The Conquest of Bread and Fields, Factories and Workshops, and his principal scientific offering, Mutual Aid: A Factor of Evolution. He also contributed the article on anarchism to the Encyclopædia Britannica Eleventh Edition.
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1.) "[T]he noblest man, the one really greatest of them all was Prince Peter Kropotkin, a self-professed atheist and a great man of science."—Ely, Robert Erskine (October 10, 1941), New York World-Telegram.