Textbook of AI

1791–1871, Mathematician, inventor; designer of the Analytical Engine

Also known as: Charles Babbage FRS

Charles Babbage was an English polymath whose Analytical Engine, designed but never completed in his lifetime, was the first conception of a general-purpose programmable computer. His earlier Difference Engine, begun in 1822, was a special-purpose mechanical calculator for evaluating polynomials by the method of finite differences. The British government funded it but the project foundered after twenty years of cost overruns and Babbage's quarrels with his chief engineer.

The Analytical Engine (designed from 1837) was a vastly more ambitious machine. It separated store (memory) from mill (arithmetic unit), used punched cards adapted from the Jacquard loom for input and program control, and supported conditional branching and loops. In the modern reading it was Turing-complete in everything but name. Babbage refined the design until his death but never built it; a working Difference Engine No. 2 was finally completed by the Science Museum in 1991.

Babbage's collaboration with Ada Lovelace produced, in her 1843 Notes, the first published description of an algorithm intended for execution by a machine, a program for computing Bernoulli numbers, and the first reflections on what such a machine could and could not do. Babbage held the Lucasian Chair of Mathematics at Cambridge from 1828 to 1839, founded the Royal Astronomical Society and the Statistical Society of London, and was a tireless campaigner against street musicians.