"Oh, but it is!" Thurmon raised himself again, with an effort. "Your study of history should have taught you one thing, if nothing else. The tempo is quickening. While it took mankind thousands of years to move from the bow and arrow to the rifle, it took only a few hundred to move from the rifle to the thermonuclear weapon. It took ages before men mastered flight, and then in two generations they developed satellites; in three, they reached the moon and Mars." "But we're talking about _physical_ development." "I know. And physically, the human race altered just as drastically in an equally short span of time. As recently as the nineteenth century, the incidence of disease was a thousandfold greater than it is now. Life was short then. In the twentieth century disease lessened and life-expectancy doubled, in certain areas. Height and weight increased perceptibly with every passing decade. Then came Leffingwell and his injections. Height, weight, life-expectancy have fallen perceptibly every decade since then. The war merely hastened the process." "You appear to have devoted a great deal of time to this question," Littlejohn observed. "I have," answered the older man. "And it is not a question. It is a fact. The one fact that confronts us all. If we proceed along our present path, we face certain extinction in a very short time. The strain is weakening constantly, the vitality is draining away. We sought to defeat Nature--but the Naturalists were right, in their way." "And the solution?" Thurmon was silent for a long moment. Then, "I have none," he said. "You have consulted the medical authorities?" "Naturally. And experiments have been made. Physical conditioning, systems of exercise, experimentation in chemotherapy are still being undertaken. There's no lack of volunteers, but a great lack of results. No, the answer does not lie in that direction." "But what else is there?" "That is what I had hoped you might tell me," Thurmon said. "You are a scholar. You know the past. You speak often of the lessons of history--" Littlejohn was nodding, but not in agreement. He was trying to comprehend. For suddenly the conviction came to him clearly; Thurmon was right. It was happening, had happened, right under their smug noses. The world was weakening. It was slowing down, and the race is only to the swift. He cursed himself for his habit of thinking in platitudes and quotations, but long years of study had unfitted him for less prosaic phraseology. If he could only be practical. _Practical._ "Thurmon," he said. "There is a way. A way so obvious, we've all overlooked it--passed right over it." "And that is--?" "Stop the Leffingwell injections!" "But--"