For this view of nature as full of nothing but darkness and cruelty, where, as Hobbes had put it, there waged “the war of every one against everybody,” the great authority of Darwin was invoked. In fact, Darwin was supposed to be almost solely responsible for the theory, and its overthrow by Kropotkin was heralded by the uninformed as another of those “death-blows” of which Darwinism is thought to have received so many during the last quarter of a century. Kropotkin, however, in his introduction, claims that the idea of mutual aid is “in reality, nothing but a further development of the ideas expressed by Darwin in the ‘Descent of Man’”. Darwin said: “Those communities which included the greatest number of sympathetic members would flourish best, and rear the greatest number of offspring.” Kropotkin complains that Darwin did not sufficiently develop this idea, but over-emphasized the idea of “competition” for life, and this error, he insists, was further accentuated by his disciples. “It happened with Darwin’s theory,” he says, “as it always happens with theories having any bearing upon human relations. Instead of widening it according to his own hints, his followers narrowed it still more.” It is a mistake to suppose that Kropotkin denies the Darwinian principle of mutual struggle. “It is evident,” says he, “that no review of evolution can be complete unless these two dominant currents are analyzed. * * * The struggles between these two forces make, in fact, the substance of history.” He anticipates the objection that his work only emphasizes the principle of mutual aid by insisting that the principle of struggle has “already been analyzed, described, and glorified from time immemorial. In fact, up to the present time, this current alone has received attention from the epical poet, the annalist, the historian, and the sociologist.” The main body of his book is a solid mass of evidence of the existence of mutual aid everywhere in the living world, from the lowest insects to the highest mammals; and from the first stone age to the twentieth century. It consists of eight chapters, the first two of which are devoted to “Mutual Aid among Animals.” Here, the theory of the human origin of society is utterly demolished. Complex social arrangements, popularly supposed to be limited to ants and bees, are shown to flourish everywhere, especially among birds.