=A Four-Grade School.= It is impossible to watch the growth of the love-life of a human being, to trace its development from babyhood up to its culmination in mating and parenthood, without a sense of wonder at the steady purpose behind it all. We used to believe that the love for the young girl that suddenly blooms forth in the callow youth was an entirely new affair, something suddenly planted in him as he developed into manhood; but now we know, thanks to the uncovering of human nature by the painstaking investigations of the psycho-analytic school of psychologists, that the seeds of the love-life are planted, not in puberty, but with the beginning of life itself. Looked at in one way, all infancy and childhood are a preparation, a training of the love-instinct which is to be ready at the proper time to find its mate and play its part in the perpetuation of the race. Nature begins early. As she plants in the tiny baby all the organs that shall be needed during its lifetime, so she plants the rudiments of all the impulses and tendencies that shall later be developed into the full-grown instincts. There have been found to be four periods in the love-life of the growing child, three of them preparatory steps leading up to maturity; periods in which the main current of love is directed respectively toward self, parents, comrades, and finally toward lover or mate. =Like Narcissus.= In the first stage, the baby's interest is in his own body. He is getting acquainted with himself, and he soon finds that his body contains possibilities of pleasurable sensations which may be repeated by the proper stimulation. Besides the hunger-satisfaction that it brings, the act of sucking is pleasurable in itself, and so the baby begins to suck his thumb or his quilts or his rattle. Later, this impulse to stimulate the nerves about the mouth finds its satisfaction in kissing, and still later it plays a definite part in the wooing process; but at first the child is self-sufficient and finds his pleasure entirely within himself. Other regions of the body yield similar pleasure. We often find a tiny child rubbing his genital organs or his thighs or taking exaggerated pleasure in riding on someone's foot in order to stimulate these nerves, which he has discovered at first merely by chance. When he begins to run around, he loves to exhibit his own body, to go about naked. None of this is naughtiness or perversion; it is only Nature's preparation of trends that she will later need to use. The child is normally and naturally in love with himself.[11] But he must not linger too long in this stage. None of the channels which his life-force is cutting must be dug too deep, else in later life they will offer lines of least resistance which may, on occasion, invite illness or perversion. [Footnote 11: This is the stage which is technically known as auto-eroticism or self-love.]