A paradox in Decision Theory. Given two boxes, B1 which contains $1000 and B2 which contains either nothing or a million dollars, you may pick either B2 or both. However, at some time before the choice is made, an omniscient Being has predicted what your decision will be and filled B2 with a million dollars if he expects you to take it, or with nothing if he expects you to take both.

**References**

Gardner, M. *The Unexpected Hanging and Other Mathematical Diversions.* Chicago, IL: Chicago University Press,
1991.

Gardner, M. ``Newcomb's Paradox.'' Ch. 13 in *Knotted Doughnuts and Other Mathematical Entertainments.*
New York: W. H. Freeman, 1986.

Nozick, R. ``Reflections on Newcomb's Paradox.'' Ch. 14 in Gardner, M. *Knotted Doughnuts and Other Mathematical
Entertainments.* New York: W. H. Freeman, 1986.

© 1996-9

1999-05-25