Many people over the years have attempted to explain human behaviour, both the Why and the How. It’s a fascinating topic. Mostly, some very perceptive and talented person has thought deeply about what goes on inside them, and checked it out with others to see if their explanation fits with what seems to happen for others.Control Theory truly is different. Its origin is in the field of engineering and science, when during the Industrial Revolution at the end of the 19th century, physicists, engineers and other scientists began looking for ways to make machines that would behave like people – the key aspect of the new machine would be that it would be able to complete a particular task, EVEN IF in some way what it had to deal with didn’t remain the same.

So the challenge was to create a machine that could still be in control in a changing environment.

William Powers, in the 1930’s, took an intuitive look at what was happening. It had become possible to design a machine that could control; he then asked himself, “If this information allows us to build a machine that can control a particular variable in a changing environment (i.e., behave like a person), what can we learn about how the person behaves? He took the control theory diagram, and tested the hypothesis that people might run similar circuits, and behave to control their perception of what was happening so that it would match a reference (i.e. an idea of what they wanted) that they had stored in their brain.

This is not a new idea to an engineer! An air conditioner, for example, works on this principle. We give it a reference (the temperature it is to control for), and its job is then to compare the temperature it senses in the environment with that reference temperature. If there is a difference between the two, it gets a signal to behave – and it turns the heating/cooling off or on to reduce the difference (error) to zero. It is controlling its perception of the environment to match its reference.

Powers found that he could prove that people operate the same way – of course, people are nowhere near as simple as the air conditioner controller, but his Control Systems Group, by setting up experiments and hypothesising about how people would behave in particular situations, has been able to demonstrate the accuracy of his theory. He now refers to the theory as Perceptual Control Theory because of the importance of perception in behaviour.

His book, “Making Sense of Behaviour” (see Books) is thought provoking and contains many stimulating ideas.

A visit to the Control Systems Group website will take you more deeply into Perceptual Control Theory.