ABSTRACT
What does the nature, i.e., the brain as the part of the nature, use to create control of any organ? It uses evidently information about the error " of the real organ behavior Y (:) relative to its desired behavior Yd (:). But, this is not the only information that the brain uses to create the control. For example, in order to control the position of a hand, of a …nger, of a leg, the brain uses information about the di¤erence between their desired and real positions, which is information about their position errors. However, the brain simultaneously uses information about the forces of the muscles acting on the organs. The muscle force is a control variable. The brain, as the central part of the natural controller , uses information about the (realized) control itself. This is one essential characteristic of the control created by the brain, i.e., by the nature. The brain, in general the nature, does not have any information about a
mathematical model of the controlled organ. This is another crucial characteristic of the control created by the brain, i.e., by the nature.
