Von Neumann announced these conclusions in 1948, and his work inspired a completely new research field that today is already divided into disciplines and is collectively known as Artificial Life. A parallel, but different, field is that of Artificial Intelligence, and it is important to keep them apart. Artificial Intelligence studies a characteristics that in real life appeared at the end of evolution, whereas Artificial Life simulates what appeared at the beginning (Sipper, 1998; Tempesti et al., 1998).
In the field of Artificial Life we are today at a level that organic life reached about 4 billion years ago, at the time of the so-called primordial soup, but the interesting thing is that we could actually wittness the origin of this new form of life with our own eyes. This is the last frontier of mechanism, the borderline beyond which the dream could became true.

The autopoietic cell

Artificial Life is an entirely new approach to some fundamental problems of biology, because it allows us to study life in a totally different way, i.e. by building machines that have some of its properties. It must be underlined, however, that silicon-based life is utterly different from carbon-based life, if nothing else because artificial molecules and artificial cells are made of electronic circuits, and are therefore two-dimensional creatures.
This explains why biologists have not abandoned more traditional approaches, and the search for a proper definition of organic life has never stopped. In this field, an important step forward was made in 1974 by Francisco Varela, Humberto Maturana and Ricardo Uribe, with the paper that introduced in biology the concept of autopoiesis.
In order to illustrate their idea, Varela and Maturana used the tale (already exploited by Aleksander Oparin) of a greenman from Mars that comes to earth and wants to discover what kind of life does exist on our planet. He makes a long list of terrestrial objects but is not so sure about their living status, and asks a farmer to help him.