Authors:

The optimum population is modeled on the iceberg- eight-ninths below the water line, one-ninth above.

Peter Edgerly Firchow, Aldous Huxley (1984). “The end of Utopia: a study of Aldous Huxley's Brave new world”, Bucknell Univ Pr
The optimum population is modeled on the iceberg- eight-ninths below the water line, one-ninth above.