When a place gets crowded enough to require ID's social collapse is not far away. It is time to go elsewhere. The best thing about space travel is that it made it possible to go elsewhere.
Robert Anson Heinlein (July 7, 1907 – May 8, 1988) was an American science-fiction writer. Often called the "dean of science fiction writers", his controversial works continue to have an influential effect on the genre, and on modern culture more generally.
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