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