Introduction

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! […]

Bill Powers

Perceptual Control Theory at 40

This intro to PCT is slanted toward those coming into to this subject from the physical sciences. Bill Powers develops an argument that leads from conventional views of behavior to the new view that PCT gives us, emphasizing in the end the odd role that organisms, seen through the eyes of PCT, play in a world otherwise dominated by physical laws. The point will be to show that control theory provides us with the germ of a radically new understanding, a break with all traditional theories of behavior—and many new ones as well […]

Bill Powers

An Introduction to Perceptual Control Theory— Standing at the Crossroads

Many people have some sense of what control is about, but very few understand clearly how control works and even fewer (including control engineers) understand clearly what a control systems controls: Not “output” or “action” but perception of whatever is being controlled; that which action accomplishes. When you stop to think about it, you realize that a control system knows nothing about output or actions; it “knows” only what it senses. The distinction may seem trivial, but the consequences are profound. Bill Powers puts it all in context. […]

I control therefore I am therefore I control
Introduction

Once around the loop

Elements of the control loop have been labeled slightly different by different people at different times and for different purposes, whether for a very plain explanation or for more mathematical treatment of the physical functions.  […]

Geese flying
Introduction

PCT in 11 steps

Control is a process of acting on the world we perceive to make it the way we want it to be, and to keep it that way. Examples of control: standing upright; walking; steering a car; scrambling eggs; scratching an itch; knitting socks; singing a tune. Extruding a pseudopod to absorb a nanospeck of food (all organisms control, not only human beings). The smallest organisms control by biochemical means, bigger ones by means of a nervous system. […]