Relay logic was certainly used prior to this. For example elevator call logic goes back to the 20s: http://elevation.wikia.com/wiki/Elevator_control_system ht

Relay logic was certainly used prior to this. For example elevator call logic goes back to the 20s: http://elevation.wikia.com/wiki/Elevator_control_system http://elevation.wikia.com/wiki/Elevator_control_system Clearly the engineers involved had some way to think about it, but I suspect were not scholarly enough to write a paper about it. (not that I've researched this.. perhaps there were earlier papers). Edit: Well here is a patent: https://patentimages.storage.googleapis.com/82/ae/57/d431cf0f65e923/US1904647.pdf https://patentimages.storage.googleapis.com/82/ae/57/d431cf0... David Lindquist was Otis's lead engineer..