The work of the famous theorist and organizer of anarchism Pyotr Alekseevich Kropotkin. After 1917, it was published only fragmentarily in several collections, in particular, in the book “Anarchy”. In the field of biology, Kropotkin’s ideas about mutual assistance as a factor of evolution, about the absence of intraspecific struggle, represented the development of one of the important directions of Darwinism. Kropotkin transferred his teaching about mutual assistance and support, about the absence of intraspecific struggle, to public life. Along with this, he recognized that both biological and social life are imbued with the beginning of struggle. But social struggle is fruitful and progressive only when it helps the emergence of new forms based on the principles of justice and solidarity. The law of mutual assistance formulated by the scientist formed the basis of his ethical teaching, which he developed in his unfinished work “Ethics”.