Benjamin Franklin Plays Sudoku

Only in the last five years has sudoku been capturing people's recreational time. But 250 years ago, Benjamin Franklin was developing fascinating puzzles with principles quite similar to sudoku, keeping himself occupied while taking a break from his electrical investigations. Now, a mathematician has discovered two Franklin puzzles even more fantastic than those previously known and written a book describing all of Franklin's mathematical endeavors.

In Benjamin Franklin's Numbers: An Unsung Mathematical Odyssey (Princeton University Press, 2007), Paul C. Pasles of Villanova University in Pennsylvania argues that Franklin's mathematical achievements have long been overlooked. Franklin applied common-sense quantitative reasoning in many areas where it had never been used—for example, calculating the economic costs of war and slavery, and making population forecasts before the field of population demographics had been developed.