Bill Powers

Modeling systems

William T. Powers (2009) We hear quite a lot about models such as weather models which can be used to predict what will happen in the next few days, or models of colliding galaxies which […]


Perceptual Control Theory Demonstrations

The following websites provide demonstrations of the mechanism of perceptual control. Repository of computer programs developed by WIlliam T. Powers, referenced in Living Control Systems III. Adam Matic’s demo programs for your browser are […]


Understanding and Changing the Things You Do

“Wow.  I am impressed with this book!  It is comprehensive, neatly structured, and provides a great scientific context for introducing Perceptual Control Theory to the layperson.  The explanation builds up gradually over the chapters.  Fantastic.” – Warren Mansell, DPhil, DClinPsy, CPsychol […]


Quick guide to getting started with PCT

Perceptual Control Theory (PCT) has been around for over 50 years, leaving a trail of papers, books, websites, posts, conversations, videos all over the web. This is a quick guide to get started with the most basic materials: introductory texts, books, demonstrations, papers, websites and finding others interested in PCT. Welcome! […]

International Association for Perceptual Control Theory

New website

We proudly present to you our new IAPCT website. This site is build in wordpress by Eva de Hullu and Matias Salgado. The purpose of the site is to provide a web portal for knowledge […]

Bill Powers

A New Muscle Model

If you are going to reverse engineer and then simulate living organisms and how they move about, it is important to simulate all the physics correctly, such as the ray tracing included in the Little Man. Here is a paper that offers significant improvements regarding simulating the actions of muscles. […]