A passage from McCulloch (1952) that nearly suggests Good's intelligence explosion of 1959:

Von Neumann has already made... a most fascinating proposal... It is natural for us to suppose that if a machine of a given complexity makes another machine, that second machine cannot require any greater specification than was required for the first machine, and will in general be simpler. All our experience with simple machines has been of that kind. But when the complexity of a machine is sufficiently great, this limitation disappears. A generalized Turing machine, coupled with an assembling machine and a duplicator of its tape, could pick up parts from its environment, assemble a machine like itself and its assembling machine and its duplicator of program, put the program into it, and cut loose a new machine like itself... [And] as it is inherently capable of learning, it could make other machines better adapted to its environment or changing as the environment changed.