It was included in The Science Fiction Hall of Fame, Volume Two after being voted one of the best novellas up to 1965. 

 Plot

The human population is now 3 million highbred elite and 5 billion Morons, and the "average" IQ is 45 (whereas now an IQ score of 100 is average, by definition). Several generations before the onset of the story, the small number of remaining 100-and-higher-IQ technocrats work feverishly to keep the morons alive. 

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