by mankind from its extremely long evolution, play even now in our modern society, which is supposed to rest upon the principle: "every one for himself, and the State for all," but which it never has succeeded, nor will succeed in realizing.

It may be objected to this book that both animals and men are represented in it under too favourable an aspect; that their sociable qualities are insisted upon, while their anti-social and self-asserting instincts are hardly touched upon. This was, however, unavoidable. We have heard so much lately of the "harsh, pitiless struggle for life," which was said to be carried on by every animal against all other animals, every "savage" against all other "savages," and every civilized man against all his co-citizens—and these assertions have so much become an article of faith—that it was necessary, first of all, to oppose to them a wide series of facts showing animal and human life under a quite different aspect. It was necessary to indicate the overwhelming importance which sociable habits play in Nature and in the progressive evolution of both the animal species and human beings: to prove that they secure to animals a better protection from their enemies, very often facilities for getting food and (winter provisions, migrations, etc.), longevity, therefore a greater facility for the development of intellectual faculties; and that they have given to men, in addition to the same advantages, the possibility of working out those institutions which have enabled mankind to survive in its hard struggle against Nature, and to progress, notwithstanding all the vicissitudes of its history. It is a book on the law of Mutual Aid, viewed at as one of the chief factors of evolution—not on all factors of evolution and their respective values; and this first book had to be written, before the latter could become possible.

I should certainly be the last to underrate the part which the self-assertion of the individual has played in the evolution of mankind. However, this subject requires, I believe, a much deeper treatment than the one it has hitherto received. In the history of mankind, individual self-assertion has often been, and continually is, something quite different from, and far larger and deeper than, the petty, unintelligent narrow-mindedness, which, with a large class of writers, goes for "individualism" and "self-assertion." Nor have history-making individuals been limited to those whom historians have represented as heroes. My intention, consequently, is, if circumstances permit it, to discuss separately the part taken by the self-assertion of the individual in the progressive evolution of mankind. I can only make in this place the following general remark:—When the Mutual Aid institutions—the tribe, the village community, the guilds, the medieval city—began, in the course of history, to lose their primitive character, to be invaded by parasitic growths, and thus to become hindrances to progress, the revolt of individuals against these institutions took always two different aspects. Part of those who rose up strove to purify the old institutions, or to work out a higher form of commonwealth, based upon the same Mutual Aid principles; they tried, for instance, to introduce the principle of "compensation," instead of the lex talionis, and later on, the pardon of offences, or a still higher ideal of equality before the human conscience, in lieu of "compensation," according to class-value. But at the very same time, another portion of the same individual rebels endeavoured to break down the protective institutions of mutual support, with no other intention but to increase their own wealth and their own powers. In this three-cornered contest, between the two classes of revolted individuals and the supporters of what existed, lies the real tragedy of history. But to delineate that contest, and honestly to study the part played in the evolution of mankind by each one of these three forces, would require at least as many years as it took me to write this book.

Of works dealing with nearly the same subject, which have been published since the publication of my articles on Mutual Aid among Animals, I must mention The Lowell Lectures on the Ascent of Man, by Henry Drummond (London, 1894), and The Origin and Growth of the Moral Instinct, by A. Sutherland (London, 1898). Both are constructed chiefly on the lines taken in Buchner's Love, and in the second work the parental and familial feeling as the sole influence at work in the development of the moral feelings has been dealt with at some length. A third work dealing with man and written on similar lines is The Principles of Sociology, by Prof. F.A. Giddings, the first edition of which was published in 1896 at New York and London, and the leading ideas of which were sketched by the author in a pamphlet in 1894. I must leave, however, to literary critics the task of discussing the points of contact, resemblance, or divergence between these works and mine.

The different chapters of this book were published first in the Nineteenth Century ("Mutual Aid among Animals," in September and November 1890; "Mutual Aid among Savages," in April 1891; "Mutual Aid among the Barbarians," in January 1892; "Mutual Aid in the Medieval City," in August and September 1894; and "Mutual Aid amongst Modern Men," in January and June 1896). In bringing them out in a book form my first intention was to embody in an Appendix the mass of materials, as well as the discussion of several secondary points, which had to be omitted in the review articles. It appeared, however, that the Appendix would double the size of the book, and I was compelled to abandon, or, at least, to postpone its publication. The present Appendix includes the discussion of only a few points which have been the matter of scientific controversy during the last few years; and into the text I have introduced only such matter as could be introduced without altering the structure of the work.

I am glad of this opportunity for expressing to the editor of the Nineteenth Century, Mr. James Knowles, my very best thanks, both for the kind hospitality which he offered to these papers in his review, as soon as he knew their general idea, and the permission he kindly gave me to reprint them.

Bromley, Kent, 1902.

CHAPTER I

MUTUAL AID AMONG ANIMALS

Struggle for existence. Mutual Aid a law of Nature and chief factor of progressive evolution. Invertebrates. Ants and Bees. Birds, hunting and fishing associations. Sociability. Mutual protection among small birds. Cranes, parrots.

The conception of struggle for existence as a factor of evolution, introduced into science by Darwin and Wallace, has permitted us to embrace an immensely wide range of phenomena in one single generalization, which soon became the very basis of our philosophical, biological, and sociological speculations. An immense variety of facts:—adaptations of function and structure of organic beings to their surroundings; physiological and anatomical evolution; intellectual progress, and moral development itself, which we formerly used to explain by so many different causes, were embodied by Darwin in one general conception. We understood them as continued endeavours—as a struggle against adverse circumstances—for such a development of individuals, races, species and societies, as would result in the greatest possible fulness, variety, and intensity of life. It may be that at the outset Darwin himself was not fully aware of the generality of the factor which he first invoked for explaining one series only of facts relative to the accumulation of individual variations in incipient species. But he foresaw that the term which he was introducing into science would lose its philosophical and its only true meaning if it were to be used in its narrow sense only—that of a struggle between separate individuals for