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Why mental workers keen on working into deep night?
At night, sun goes beneath the horizon -> water and nutrition in human body concentrate at feet -> nerves on feet relaxed -> muscles of feet relaxed -> heart relaxed -> brain calm down.
Q.E.D.
Then when shall we waken?
As soon as the water and nutrition are accumulated sufficiently to reach the head.
Why Human Beings Normally Sleep at Night?
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原文地址：http://www.cnblogs.com/ybing81/p/4222281.html
