# 018 A proposed evolutionary model

Now I would like to pass on from this to considering what happens when we have a whole lot of automata interacting with the food supply network on which they live. Clearly in this case, there is a perfectly good sense in which the activity of an automaton, and in particular, a species of automaton, generated by the evolution permitted as a result of their previous feeding, will structure the world around them so that this particular species alone is favored. Hence a system of this sort, and it can be argued quite rigorously, is a self-replicating system. Furthermore since these structures, being geometrically bounded, are constrained, there will be a finite size to the structures and things will tend to come apart when they reach this critical limit. What I would like to do is give a special name to this odd kind of structure, which is a close coupling between a lot of automata and the world they live in. I will call it a domain. I will suppose that the domain is an existent in this sort of system, for there is no chance to discuss it adequately at the moment. I am particularly interested in what happens to a domain when, for example, we give the elements a lot of food. I am particularly interested in this because it occurs to me this is one of the ways in which a game-theoretic explanation leads to clarity where others do not.

For example, suppose a three-space, in which we have got these creatures wandering around, and we have a domain (Fig. 10). Suppose I, as an observer, can by some miraculous means put my finger on this ephemeral entity and say that it is an organization which is wandering around, it is automata in equilibrium with their environment, which they modify, which is wandering around in a cube. Supposing I could put my finger on it in this way, I would be doing an operation, if I allowed it more food, if I favored this entity, equivalent to a linear transformation of the payoff function of the game. This is an entirely explicit thing to do. I simply add to each entry in the pay-off matrix, a small positive number. The result of this is that more automata can live within the domain, and they will be the sort of automata which happen to be playing in this region. I will be favoring just those players.