Whatever form the dinner took, wherever the dinner went, there followed the fluent, ever-changing animal organism, producing tooth or claw, tongue or proboscis, seven stomachs or a private fish-pole—whatever was necessary to lure, catch, hold, inclose, and assimilate, this ever-receding and sometimes actively resisting, but always indispensable dinner. The evolution of animal organisms is conditioned mainly upon the food supply. How does humanity figure in this transformation scene? Man alone, of the whole animal kingdom, has attained a complete new stage in this imperative process of nutrition. Where the most primitive ameboid cell can but receive food; where the whole machinery of later organisms can but seize food; man, and man alone, produces food. Through all the ages, through every conceivable modification of structure and function, the animal has pursued its dinner. Man has caught it. Man alone has permanently mastered his food supply; instead of an endless chase it is a closed circle—he makes that which makes him. That is why physical evolution stops with man—and psychical evolution begins. No longer at the mercy of thin grass, man makes the fat-grained corn; no longer endlessly chasing the buffalo, he raises the big steer. His prairie in the garden, his prey in the barnyard, the animal can rest at last, and man can grow. By what strange new power is this immense step taken, which has enabled this one out of all created forms to apply productive force, instead of mere destructive force, to his food supply? By the power of organisation. By entering upon that new life, the social life, which raises us above all lower forms. The cell groups with others into the organ, the organs group again and form organisms; the organisms, once more combined, form an organisation. Society is the fourth power of the cell. A low and limited form of social life began with the temporary union of hunters; loose fluctuating hordes, like those of wild dogs or wolves. When cattle were kept instead of killed, were milked and sheared and bred with care and forecast, there arose a higher group form, the family. With an insured food supply at hand man sat quiet, watching his cattle; and with food to spare and time to spare, he began to grow. The family, our physical nucleus, grew too; grew as it had never grown before. The limits of cattle-fed life were sharp and clear. There was no permanent home, no village, no extra-familiar intercourse, only warfare over pasture and water between tribe and tribe. But the hour came when corn was planted and eaten; and then our human life was indeed established.