William T. Powers


William T. Powers was a medical physicist and an independent scholar of experimental and theoretical psychology who developed the perceptual control theory model of behavior as the control of perception. PCT demonstrates and explains how rather than controlling their behavioral outputs, living things vary their behavior as the means of controlling their sensory inputs. Living control systems differ from those specified by Engineering control theory, for which the reference value for control is specified outside the system by what is called the controller, whereas in living systems the reference variable for each feedback control loop in a control hierarchy is generated within the system, usually as a function of error output from a higher-level system or systems. Powers and his students and colleagues in diverse fields have developed many demonstrations of negative feedback control, and computer models or simulations that replicate observed and measured behavior of living systems with a very high degree of fidelity, and corresponding control structures have been demonstrated neurophysiologically.
Powers also designed the board game Trippples, produced by Aladdin Industries and granted US Patent 3,820,791 in 1974

Selected bibliography