George Boole and the Algebra of True and False

George Boole was born on November 2, 1815, the son of a shoemaker who mostly taught himself mathematics. He showed that reasoning could be written as algebra, where every statement is either true or false and words like AND, OR, and NOT work like plus and minus. A century later, engineers built computer circuits on his rules, and every phone and laptop still runs on them. Careful thinking, written down clearly, can outlast its author by centuries.

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