For example, we might regard each person in the room as a subautomaton and the environment as consisting of one or more additional subautomata. As we shall see, this representation has many of the qualitative properties of interactions among things and persons. The number of states required in the subautomata is very large, for example , if we try to represent a person's knowledge. Automata this large have to be represented by systems of equations or by computer programs, or in some other way that does not involve mentioning states individually. In Section 4 we'll represent them partially, by sentences of logic.
Geometric information is hard to represent.
The system of fixed interconnections is inadequate. Since a person may handle any object in the room, an adequate automaton representation would require signal lines connecting him with every object. Namely, we do not ever know a person well enough to list his internal states. The kind of information we do have about him needs to be expressed in some other way. Let us consider the notion of can .