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If we killed all the idiots all of us would be dead.
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QUOTE
by killing off those who don't pass a certain score on an IQ test?
Anyways, this is almost exactly what my made-up society would do if I were to make an "ideal" society.
Except instead of an IQ Test, it would be an Age 12 test.
Anyone that does not pass is either killed, or shipped away to some island or something. If they can survive on that island for another four years without outside assistance, then they're let back in.
But lastly, if it were for the sake of "natural selection", it should be many tests, some physical and some mental, and then you take the scores, and if the average, or combined, or whatever you want to do, score doesn't add upto or higher than X, you die.