rom all restraint. Each
individual creature devours as much as it can and feeding, together
with propagation by division, "budding" or conjunction, makes up the
total of its vital activities. It need do no more to accomplish the
purpose of its existence. Even when propagation commences to take
place by means of individual male and female parents, the same
principle of egoism largely obtains. The spiders are typical instances
of this: in their case the carrying out of the natural functions of
the male spider is attended with much danger for him, owing to the
fact that if he does not exercise the greatest care, he is apt to be
devoured immediately afterward by his female partner, in order that no
useful food matter may be lost. Yet even in the case of the spiders,
the female spider already gives proof of a certain capacity for
sacrifice where her young are concerned, at any rate for a short time
after they have crept from the egg.

In animals somewhat higher in the creative scale, more or less
powerful feelings of affection may develop out of their sex
association. There is affection on the part of the male for his mate,
and on the part of the female for her young. Often these feelings
develop into a strong, lasting affection between the sexes, and years
of what might be called faithful matrimonial union have been observed
in the case of birds. This in itself is sufficient to establish the
intimate relationship between love in a sex sense and love in a
general sense. And even in the animal creation we find the same
analogy existing between these feelings of sympathy and their
opposites which occur in the case of human beings. Every feeling of
attachment or sympathy existing between two individuals has a
counterpart in an opposite feeling of discontent when the object of
the love or attachment in question dies, falls sick, or runs away.
This feeling of discontent may assume the form of a sorrow ending in
lasting melancholy. In the case of apes and of certain parrots, it has
been noticed that the death of a mate has frequently led the survivor
to refuse nourishment, and die in turn from increasing grief and
depression. If, on the other hand, an animal discovers the cause of
the grief or loss which threatens it; if some enemy creature tries to
rob it of its mate or little ones, the mixed reactive feeling of rage
or anger is born in it, anger against the originator of its
discontent. Jealousy is only a definite special form