"Dell was a critical tributary. You, Dr. Curtis Johnson, are another. Changing or destroying such key individuals snips off branches of knowledge before they come into fruit." It was an ungraspable answer, but it had to be argued against because of its conclusion. "The scientists are not bringing about the war," Curt said, looking from one fleshless face to another. "Find the politicians responsible, those willing to turn loose any horror to gain power. _They_ are the ones you want." "That would mean destroying half the human race. In your day, nearly every man is literally a politician." "Talk sense!" Curt said angrily. "A politician, as we have come to define him, is simply one willing to sacrifice the common good for his own ends. It is a highly infectious disease in a day when altruism is taken for cowardice or mere stupidity. No, we have not mistaken our goal, Dr. Johnson. We cannot hasten the maturity of the race. We can only hope to take the matches away so the children cannot burn the house down. Whatever you doubt, do not doubt that we are from the future or that we caused Dell's death. He is only one of many." Curt slumped. "I did doubt it. I still do, yet not with conviction. Why?" "Because your own sense of guilt tells you that you and Dell and others like you are literally the matches which we have to remove. Because your knowledge of science has overcome your desire not to believe. Because you _know_ the shape of the future." "The war after the Third World War--" Curt murmured. "Someone said it would be fought with stones and spears, but your weapons are far from stones and spears." "Perhaps not so far at that," said Sark, his face twisting wryly. He reached to a nearby table and picked up a tomato and a carrot. "These are our weapons. As humble and primitive as the stones and spears of cavemen." * * * * * "You're joking," Curt replied, almost ready to grin. "No. This is the ultimate development of biological warfare. Man is what he eats--" "That's what Dell's sign said." "We operate hundreds of gardens and farms such as Dell's. We work through the fertilizing compounds we supply to these farms. These compounds contain chemicals that eventually lodge in the cells of those who eat the produce. They take up stations within the brain cells and change the man--or destroy him. "Certain cells of the brain are responsible for specific characteristics. Ways of altering these cells were found by introducing minute quantities of specific radioactive materials which could be incorporated into vegetable foods. During the Third War wholesale insanity was produced in entire populations by similar methods. Here, we are using it to accomplish humane purposes. "We are simply restraining the scientists responsible for the destroying weapons that produced our nightmare world. You saw the change that took place in Dell. There is a good example of what we do."