Before revision:  It is assumed that the brain makes an internal estimate of an individual's own evolutionary fitness, which can be shown to produce an irreducible, distinct cause . Communicating components of the fitness estimate (either for external or internal use) requires inverting them.
After revision:  It is assumed that the brain makes an internal estimate of an individual's own evolutionary fitness, which can be shown to produce a special, distinct form of causation . Communicating components of the fitness estimate (either for external or internal use) requires inverting them.