“Shannon was interested in building a machine that could play chess—and more generally in building mechanisms that imitated thought. In 1940, he published his master’s thesis, which was titled “A Symbolic Analysis of Relay Switching Circuits.” In it, he showed that it was possible to build electrical circuits equivalent to expressions in Boolean algebra. In Shannon’s circuits, switches that were open or closed corresponded to logical variables of Boolean algebra that were true or false. Shannon demonstrated a way of converting any expression in Boolean algebra into an arrangement of switches.”