Letter to Max Born, 4 Dec. 1926, in Einstein und Born Briefwechsel (1969) p. 130 (often quoted as Gott wrfelt nicht God does not play dice, e.g. in B. Hoffmann Albert Einstein (1973) ch. 10)
"What Are You Going to Do With That?". Essay adapted from a talk delivered to a freshman class at Stanford University in May 2010, www.chronicle.com. October 03, 2010.