Any process located above another process may be a goal process that rewards,
allowing the function before it to evolve. We refer to a function that maximizes
a goal function as maximally useful. For an informative function to be learned
genetically, it must support a goal which is relatively constant in the species, with
evolution leading toward it becoming maximally useful. Goal processes often contribute toward reproductive behavior or are survival related. Communication
processes produce results with the systems in which they occur such that similar
processes are as likely or more likely to survive and reproduce than they were
before. This is because introducing communicative capabilities essentially makes
a system larger, which can lead to increased self-organization, than would be the
case with individual, smaller, non-communicative systems.
Given our model of communication, communication systems are likely to develop
in self-organizing systems because of their support for what are conceptually
larger systems, leading to more self-organization and increased adaptability.
We assume that it is almost as likely that if one process evolves then its inverse
will also evolve. We also assume that information about another system may be
beneficial to the system in question under many circumstances and thus communication
systems are evolutionarily adaptive.