We have confidence in our science-based civilization and think it has tenure. In so doing, I think we fail to distinguish between the life-span of civilizations and that of our species. In fact, civilizations are ephemeral compared with species. Humans have lasted at least a million years, but there have been 30 civilizations in the past 5000 years. Humans are tough and will survive; civilizations are fragile. It seems clear to me that we are not evolving in intelligence, not becoming true Homo sapiens. Indeed there is little evidence that our individual intelligence has improved through the 5000 years of recorded history.

Humans will survive the death of civilization, which has happened 30 times over the centuries.

\"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 that\'s to keep the savages from getting the goods before they\'re ready.\"

An alien species that suffers regular collapses of civilization due to overpopulation keeps their museums out in the middle of nowhere and under bomb-proof domes to protect their contents so future savages may rediscover them and rebuild from their predecessors.