**And whereas John Preskill firmly believes that a mechanism
for the information to be released by the evaporating black hole must and
will be found in the correct theory of quantum gravity,**

**Therefore Preskill offers, and Hawking/Thorne accept,
a wager that:****
**

When an initial pure quantum state undergoes gravitational collapse to form a black hole, the final state at the end of black hole evaporation will always be a pure quantum state.

**The loser(s) will reward the winner(s) with an encyclopedia
of the winner's choice, from which information can be recovered at will.**

**Stephen W. Hawking, Kip S. Thorne, John P. Preskill**
**Pasadena, California, 6 February 1997**