Gottfried Wilhelm Leibniz

Gottfried Wilhelm Leibniz

A German polymath who built the stepped reckoner in the 1670s, the first mechanical calculator able to perform all four arithmetic operations, and who set out modern binary arithmetic in his 1703 essay Explication de l'Arithmétique Binaire. More ambitiously, he imagined a characteristica universalis, a formal symbolic language in which any argument could be written down, and a calculus ratiocinator, a mechanical procedure for settling disputes by calculation rather than debate. That pairing of a formal notation with a mechanical rule for manipulating it is the ancestor of both symbolic logic and the stored-program computer. (See also: Charles Babbage, Symbolic AI, Algorithm)