One could say that a man can “inject” an idea into the machine, and that it will respond to a certain extent and then drop into quiescence, like a piano string struck by a hammer. Another simile would be an atomic pile of less than critical size: an injected idea is to correspond to a neutron entering the pile from without. Each such neutron will cause a certain disturbance which eventually dies away. If, however, the size of the pile is sufficiently increased, the disturbance caused by such an incoming neutron will very likely go on and on increasing until the whole pile is destroyed. Is there a corresponding phenomenon for minds, and is there one for machines? … Adhering to this analogy we ask, “Can a machine be made to be supercritical?
— Turing, Alan M. “Computing Machinery and Intelligence.” Mind 59 (1950): 433-60.
