the same family. The latter may lead to parricide, fratricide,
infanticide, or assassination of a conjoint.

=Phylogeny of Love.=--The social life of ants offers us some
instructive analogies. In spite of the intense hostility of different
colonies of ants among themselves, there may be obtained by habitude,
often after many desperate combats, alliances between colonies which
were hitherto enemies, even between colonies of different species.
These alliances henceforth become permanent. This is very curious to
observe at the time when the alliance begins to be formed. We then see
certain individual hatreds persist, to a varying extent, for several
days. Certain individuals of the weaker party are maltreated by other
individuals of the conquering party. They cut off their limbs and
antennae and often martyrize them to death with a rabidness that sadly
resembles human sentiments! Hatred and dispute between individuals of
the same colony of ants are, on the other hand, extremely rare. I can
guarantee the correctness of all these observations, having often
repeated them myself and having recorded them in my works on the
habits of ants. Moreover, they have since been confirmed by other
writers.

After what we have just said, and especially if we take into
consideration the numerous observations which have been made in
biology, we can hardly doubt that the sentiment of sexual attraction,
or the sexual appetite, has been the primary source of nearly all, if
not all, the sentiments of sympathy and duty which have been developed
in animals and especially in man. Many of these sentiments are no
doubt little by little completely differentiated and rendered entirely
independent of sexual sentiment, forming a series of corresponding
conceptions adapted to divers social objects in the form of sentiments
of amity. The latter in their turn have often become the generators of
social formations and of a more generalized altruism. Many others,
however, have remained more or less consciously associated with the
sexual appetite, as is certainly the case in man.

This short sketch which we have given of the phylogenetic history of
love and its derivatives is sufficient to show the immense influence
which sexual life has exercised on the whole development of the human
mind.

On the other hand, we must avoid exaggerating the actual importance of
this influence. Young children, who possess neither sexual appetite
nor corresponding sensation