'Mutual Aid: A Factor of Evolution ' Summary

Mutual Aid is considered a fundamental text in anarchist communism. It presents a scientific basis for communism as an alternative to the historical materialism of the Marxists. Kropotkin considers the importance of mutual aid for prosperity and survival in the animal kingdom, in indigenous and early European societies, in the Medieval free cities (especially through the guilds), and in the late 19th century village, labor movement, and poor folk. He criticizes the State for destroying historically important mutual aid institutions, particularly through the imposition of private property.

Many biologists also consider it an important catalyst in the scientific study of cooperation.

Daniel P. Todes, in his account of Russian naturalism in the 19th century, concludes that Kropotkin's work "cannot be dismissed as the idiosyncratic product of an anarchist dabbling in biology" and that his views "were but one expression of a broad current in Russian evolutionary thought that pre-dated, indeed encouraged, his work on the subject and was by no means confined to leftist thinkers."

Kropotkin emphasizes the distinction between competitive struggle between individual organisms over limited resources and collective struggle between organisms and the environment. He drew from his first hand observations of Siberia and Northeast Asia, where he saw that animal populations were limited not by food sources, which were abundant, but rather by harsh weather. For example, predatory birds may compete by stealing food from one another while migratory birds cooperate in order to survive harsh winters by traveling long distances. He did not deny the competitive form of struggle, but argued that the cooperative counterpart has been under-emphasized: "There is an immense amount of warfare and extermination going on amidst various species; there is, at the same time, as much, or perhaps even more, of mutual support, mutual aid, and mutual defense...Sociability is as much a law of nature as mutual struggle."

As a description of biology, Kropotkin's perspective is consistent with contemporary understanding. Stephen Jay Gould admired Kropotkin's observations, noting that cooperation, if it increases individual survival, is not ruled out by natural selection, and is in fact encouraged. Kropotkin's ideas anticipate the now recognized importance of mutualism (a beneficial relationship between two different species) and altruism in biology. Examples of altruism in animals include kin selection and reciprocal altruism. Douglas H. Boucher places Kropotkin's book as a precursor to the development of the biological theory of altruism.