William T. Powers

William T. Powers (August 29, 1926 - May 24, 2013) was an independent scientist^[1] who developed perceptual control theory (PCT). PCT posits, and demonstrates, that living things do not control their behavior, but rather their behavioral outputs are the variable means by which they control their sensory inputs (perceptions). Engineering control theory differs from PCT by specifying a separate controller external to the system, whereas in living systems the reference variable for each control loop in a control hierarchy is set from within the system. 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 (human and animal, individuals and groups of individuals) with a very high degree of fidelity (0.95 or better).

Selected Bibliography

• Powers, William T. (1973). Behavior: The control of perception. Chicago: Aldine de Gruyter. ISBN 0-202-25113-6. 2nd ed. (2005) New Canaan: Benchmark Publications. Chinese tr. (2004) Guongdong Higher Learning Education Press, Guangzhou, China. ISBN 7-5361-2996-3.
• Powers, William T. (1989). Living control systems. [Selected papers 1960-1988.] New Canaan, CT: Benchmark Publications. ISBN 0-9647121-3-X.
• Powers, William T. (1992). Living control systems II. [Selected papers 1959-1990.] New Canaan, CT: Benchmark Publications.
• Powers, William T. (1998). Making sense of behavior: The meaning of control. New Canaan, CT: Benchmark Publications. ISBN 0-9647121-5-6
• Powers, William T. (2008). Living Control Systems III: The fact of control. [Mathematical appendix by Dr. Richard Kennaway. Includes computer programs for the reader to demonstrate and experimentally test the theory.] New Canaan, CT: Benchmark Publications. ISBN 978-0-9647121-8-8.

External links

• The Control Systems Group

Notes