[3] Frederick Nietzsche, Thus Spoke Zarathustra, pp. 5-296. Macmillan Co., N. Y.
[4] Carl Snyder, The World Machine. New York, Longmans, Green & Co., 1907.
[5] Prestonia Mann Martin, Is Mankind Advancing? New York, Baker & Taylor Co., 1911.
[6] G. Bernard Shaw, Man and Super Man, p. 218-219. N. Y., Brentano’s.
[7] Herbert Spencer, The Data of Ethics. Para. 97. N. Y., D. Appleton & Co., 1893.
[8] Saml. Z. Batten, The Redemption of the Unfit, American Journal of Sociology, Vol. 14, p. 242 (1909).
[9] Francis Galton, Memoirs of My Life, p. 311. N. Y., E. P. Dutton, 1909.
[10] Arnold White, Efficiency and Empire, p. 97. London, Methuen & Co., 1901.
[11] W. C. & C. D. Whetham, The Family and the Nations, p. 85. N. Y., Longmans, 1909.
[12] Gustave Michaud, Shall We Improve Our Race, The Popular Science Monthly, Vol. 72, p. 77 (1908).