Cellular Automota

In his last years, von Neumann puzzled over the question of whether a machine could reproduce itself. Using an abstract model (a cellular automata), von Neumann outlined how a machine could reproduce itself from simple components. Key to this demonstration is that the machine reads its own “genetic” code, interpreting it first as instructions for constructing the machine exclusive of the code and second as data. In the second phase, the machine copies its code in order to create a completely “fertile” new machine. Conceptually, this work anticipated later discoveries in genetics.