Claude Shannon: The Playful Genius Who Invented the Bit and the Digital Age

Got something to say to this podcast? Send a voicemail, and you might hear yourself on the next episode!

Claude Shannon's garage held a flame-throwing trumpet, rocket-powered frisbees, a Rubik's Cube solving robot, and foam shoes for walking on water. The same man laid the mathematical foundation of the digital world. Born in 1916 in Gaylord, Michigan, he strung a half-mile telegraph along barbed wire fences as a boy. At MIT, working on Vannevar Bush's differential analyzer, he saw that a switch being open or closed matched the true and false of George Boole's algebra. His 1937 thesis turned circuit design from trial and error into a science.

This episode follows the ideas that came after. At Bell Labs during World War II, Shannon worked on anti-aircraft fire control and cryptography, proved the one-time pad unbreakable, and talked computing over tea with Alan Turing. In 1948 his paper A Mathematical Theory of Communication separated information from meaning, introduced the bit, and set the limits for compression and error correction. Then came a maze-learning mechanical mouse, computer chess, and decades of serious play.

• Shannon's maxim, the enemy knows the system, holds that security must rest entirely on the key, never on a secret machine.
• Theseus, the mechanical mouse he built with his wife Betty in 1950, learned a maze by trial and error and relearned it when the walls moved.
• The Shannon number puts the count of possible chess games at 10 to the 120th power, far beyond the roughly 10 to the 80th atoms in the observable universe.
• With Edward O. Thorp he built the first wearable computer, hidden in a shoe, to predict where a Las Vegas roulette ball would land.
• His rebalancing strategy, known as Shannon's Demon, kept a portfolio split evenly between cash and a volatile stock and reportedly averaged 28 percent a year.