1916–2001 · mathematician and engineer, Bell Labs and MIT

master's thesis is not usually famous. Claude Shannon's was: it showed that the algebra of logic could describe circuits of relays and switches (Shannon, 1938), which made the design of digital circuits a matter of calculation. He spent his most productive years at Bell Telephone Laboratories, and later taught at MIT.

what he did

In 1948 he published A Mathematical Theory of Communication, which defined information as a reduction in uncertainty, measured it in bits, and proved how much can be sent through a noisy channel without error. It came out as a book with an essay by Warren Weaver the next year (Shannon & Weaver, 1949). The archive introduces the paper and quotes it.

He then turned the measure on language. In a 1951 experiment (Shannon, 1951), people guessed a text letter by letter, and the pattern of their guesses gave an estimate of how predictable English is. He wrote one of the first papers on how a computer might play chess (Shannon, 1950), and in 1950 built a mechanical mouse, Theseus, that learned its way through a maze.

why he is here

The signal pages lean on his theory. Next-letter prediction, scaled up enormously, is how language models are trained; see hallucination.

in the tour: the rack room has a case labelled "Shannon, 1948" ···

Primary works and sources

1. Shannon (1938). A symbolic analysis of relay and switching circuits. Transactions of the American Institute of Electrical Engineers. doi:10.1109/t-aiee.1938.5057767
2. Shannon (1948). A Mathematical Theory of Communication. Bell System Technical Journal. doi:10.1002/j.1538-7305.1948.tb01338.x
3. Shannon & Weaver (1949). The Mathematical Theory of Communication. Urbana: University of Illinois Press.
4. Shannon (1951). Prediction and Entropy of Printed English. Bell System Technical Journal. doi:10.1002/j.1538-7305.1951.tb01366.x
5. Shannon (1950). Programming a computer for playing chess. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science. doi:10.1080/14786445008521796

see also

	archive: Shannon, 1948 — the paper, introduced
	signal — noise, information and inference
	Norbert Wiener — cybernetics, the same year