And if you do it with the right rocks, you can get out more fuel than you put in.
This is a great piece of history. The late Professor Mike Driscoll of MIT, known for his work on fission breeding (where more fuel is produced than is consumed — go figure!) asked the question of the origins of the word “breeder” to Dr. Alvin Weinberg. This is Dr. Weinberg’s response with Dr. Eugene Wigner’s handwritten addition. 12 April 1976.