Museums for Rebooting Civilization

"You don't see the point of a museum, Horst. It's for the next rise in the Cycles. Savages come to put together another civilization. The faster they can do it, the longer it'll be before another collapse because they'll be expanding their capabilities faster than the population. See? So the savages get their choice of a number of previous civilizations, and -the weapons to put a new one into action. You noticed the lock?" "I did," said Potter. "You need some astronomy to solve it. I presume...

 Economic Population Control

Senator Fowler nodded. "One other little point, Charlie. Just how often do your reproductive castes breed, anyway?" It was Jock who answered. When Charlie hesitated, David Hardy watched with interest-was there communication by gesture? "When they are allowed to," the alien said smoothly. "Don't yours?" "Eh?" "You control your populations through economic incentives and forced emigration. Neither alternative is available to us, yet our reproductive drives are no less strong than yours. Our ...