“What is love except another name for the use of positive reinforcement? Or vice versa.”

Initial statement of the Uncertainty principle in "Über den anschaulichen Inhalt der quantentheoretischen Kinematik und Mechanik" in Zeitschrift für Physik, 43 (1927)
Variant translation: The more precisely the position is determined, the less precisely the momentum is known in this instant, and vice versa.
As quoted in "The Uncertainty Principle" at the American Institute of Physics http://www.aip.org/history/heisenberg/p08.htm

Source: A Universe from Nothing, Simon & Schuster (2012), p. 151

Source: Timescape (1980), Chapter 5 (p. 46)

Response to an editor pressuring her for overdue work, as quoted in The Unimportance of Being Oscar (1968) by Oscar Levant, p. 89

The difference did not exist. Our company is too big. It goes with the welfare of the country. Our contribution to the nation is considerable.
Charles E. Wilson (1952) in: Confirmation hearings before the Senate Armed Services Committee, responding to Sen. Robert Hendrickson's question regarding conflicts of interest. Quoted in Safire's Political Dictionary (1978) by William Safire.

Source: Demian (1919), p. 147
Context: Certainly you shouldn't go kill somebody or rape a girl, no! But you haven't reached the point where you can understand the actual meaning of "permitted" and "forbidden." You've only sensed part of the truth. You will feel the other part, too, you can depend on it. For instance, for about a year you have had to struggle with a drive that is stronger than any other and which is considered "forbidden." The Greeks and many other peoples, on the other hand, elevated this drive, made it divine and celebrated it in great feasts. What is forbidden, in other words, is not something eternal; it can change. Anyone can sleep with a woman as soon as he's been to a pastor with her and has married her, yet other races do it differently, even nowadays. Each of us has to find out for himself what is permitted and what is forbidden — forbidden for him. It's possible for one never to transgress a single law and still be a bastard. And vice versa. Actually it's only a question of convenience. Those who are too lazy and comfortable to think for themselves and be their own judges obey the laws. Others sense their own laws within them; things are forbidden to them that every honorable man will do any day in the year and other things are allowed to them that are generally despised. Each person must stand on his own feet.

“Famously Rear-Ended Reality Stars,” http://barelyablog.com/?p=45750 Barely a Blog, December 17, 2011.
2010s, 2011

Kulturphilosophie (1923), Vol. 2 : Civilization and Ethics