Sexual activity, we see, is not merely a bald propagative act, nor, when propagation is put aside, is it merely the relief of distended vessels.  It is something more even than the foundation of great social institutions.  It is the function by which all the finer activities of the organism, physical and psychic, may be developed and satisfied.  Nothing, it has been said, is so serious as lust—­to use the beautiful term which has been degraded into the expression of the lowest forms of sensual pleasure—­and we have now to add that nothing is so full of play as love.  Play is primarily the instinctive work of the brain, but it is brain activity united in the subtlest way to bodily activity.  In the play-function of sex two forms of activity, physical and psychic, are most exquisitely and variously and harmoniously blended.  We here understand best how it is that the brain organs and the sexual organs are, from the physiological standpoint, of equal importance and equal dignity.  Thus the adrenal glands, among the most influential of all the ductless glands, are specially and intimately associated alike with the brain and the sex organs.  As we rise in the animal series, brain and adrenal glands march side by side in developmental increase of size, and at the same time, sexual activity and adrenal activity equally correspond.

Lovers in their play—­when they have been liberated from the traditions which bound them to the trivial or the gross conception of play in love—­are thus moving amongst the highest human activities, alike of the body and of the soul.  They are passing to each other the sacramental chalice of that wine which imparts the deepest joy that men and women can know.  They are subtly weaving the invisible cords that bind husband and wife together more truly and more firmly than the priest of any church.  And if in the end—­as may or may not be—­they attain the climax of free and complete union, then their human play has become one with that divine play of creation in which old poets fabled that, out of the dust of the ground and in his own image, some God of Chaos once created Man.

CHAPTER VII

THE INDIVIDUAL AND THE RACE

I

The relation of the individual person to the species he belongs to is the most intimate of all relations.  It is a relation which almost amounts to identity.  Yet it somehow seems so vague, so abstract, as scarcely to concern us at all.  It is only lately indeed that there has been formulated even so much as a science to discuss this relationship, and the duties which, when properly understood, it throws upon the individual.  Even yet the word “Eugenics,” the name of this science, and this art, sometimes arouses a smile.  It seems to stand for a modern fad, which the superior person, or even the ordinary plebeian democrat, may pass by on the other side with his nose