Von Neumann extended the concept of Turing’s Universal Machine to a Universal Constructor: a machine that can execute the description of any other machine, including a description of itself. The Universal Constructor can, in turn, be extended to the concept of a machine that, by encoding and transmitting its own description as a self-extracting archive, reproduces copies of itself somewhere else. Digitally encoded organisms could be propagated economically even with extremely low probability of finding a host environment in which to germinate and grow.
