Unwrapping occurs when the "solution" is explicitly built into the program from the start.

Holland's and Kauffman's work, together with Dawkins' simulations of evolution and Varela's models of autopoietic systems, provide essential inspiration for the new discipline of artificial life, This approach, initiated by Chris Langton (1989, 1992), tries to develop technological systems (computer programs and autonomous robots) that exhibit lifelike properties, such as reproduction, sexuality, swarming, and co-evolution.

nonlinear interactions almost always make the behavior of the aggregate more complicated than would be predicted by summing or averaging.

Particular individuals do not recur, but their building blocks do.

The recycling of resource by the aggregate behavior of a diverse array of agents is much more than the sum of the individual actions.

The multiplier effect is a major feature of networks and flows. It arises regardless of the particular nature of the resource, be it goods, money, or messages.

Model building is the art of selecting those aspects of a process that are relevant to the question being asked. As with any art, this selection is guided by taste, elegance, and metaphor; it is a matter of induction, rather than deduction. High science depends on this art.