though it were the only law of life, while as a matter of fact it is
but half the story. Nature has seen to it that there shall be planted
in every living creature an innate urge toward the larger life of the
race. Although the creature may never give a conscious thought to the
welfare of the race, he still bears within himself a set of instincts
which have as their end and aim, not the individual at all, but
society as a whole, and the life of generations that are to come. He
is bigger than he knows. Although he may have no notion why he feels
and acts as he does, and although he may pervert the purpose for his
own selfish end, he is continually being moved by the mighty impulse
of the race-life, an impulse which often outrivals the desire I or his
own personal existence. The craving to reproduce ourselves and the
craving to cherish and protect our young are among the most dynamic
forces in life. The two desires are so closely bound together that
they are often spoken of as one under the name of the sex-instinct, or
the family instincts. Let us look first at that part of the yearning
which urges toward perpetuating our own life in offspring.

=Watching Nature Work.= It is wonderful, indeed, to watch Nature in
the long process of Evolution, as she adapts her methods to the
growing complexity of the organism. With a variety and ingenuity of
means, but always with the same steady purpose, she works from the
lowest levels,--where there is no true reproduction, only
multiplication by division,--on through the beginning of reproduction
proper, where a single parent produces the offspring; then on to the
level where it takes two parents of different structure to produce a
new organism, and sex-life begins. At first Nature does not even
demand that father and mother shall come near each other. In the
water, the female of this type lays an egg, and the male, guided by
his instinct, swims to it and deposits his fertilizing fluid. In plant