Georg Friedrich Bernhard Riemann, “On the Hypotheses Which Lie at the Foundations of Geometry,” lecture, Gottingen Observatory, June 10, 1854.
15
E. T. Bell, Men of Mathematics (New York: Simon & Schuster, 1965), p. 21.
16
Leonard Mlodinow, Euclid's Window (New York: Simon & Schuster, 2002), p. xi.
17
Edna St. Vincent Millay, “Euclid Alone Has Looked on Beauty Bare,” quoted in Robert Osserman, Poetry of the Universe (New York: Anchor Books, 1995), p. 6.