The best idea ever in psychology

Published in NRC on 21 September 2018


Behavior change is the major challenge of our times. At least, that’s what the initiators of the mega project Behavior Change For Good are claiming.

BCFG is a new collaborative project involving some fifty scientists from various American universities. Their task: to test practical interventions in the field of health, education, and financial behavior. And their goal: to eradicate major social problems affecting large groups of people. Being overweight, for example, or the prospect of not having an adequate pension to live on.

At the recent kick-off, psychologist and Nobel prize winner Daniel Kahneman was the guest of honor. The makers of a podcast about the event asked him to share his ‘wisdom’ in the field of behavior change. Kahneman’s answer was interesting to say the least. “I’ll cite the idea that, for me, is the best idea I ever heard in psychology. It’s the story of how you induce people to change their behavior, as taught by Kurt Lewin.”

Kurt Lewin (1890-1947) was a renowned Jewish-German psychologist who emigrated to the United States and conducted research into, amongst other things, group behavior and change. He was convinced that exhibiting or not exhibiting desirable behavior was largely the result of two kinds of forces that play a role in all situations: driving forces and restraining forces. According to Lewin, our behavior is a state of equilibrium between these two kinds of forces.

Let’s imagine you want to go jogging three times a week. A driving force could then be: knowing that running regularly is healthy. A restraining force can be: too many other obligations. Kahneman: “Lewin’s insight was that if you want to achieve change in behavior, there’s a good way to do it and a bad way to do it. The good way to do it is by reducing the restraining forces, not by increasing the driving forces.”

According to Lewin’s force field theory, we often go for the wrong instrument. We start to push. We try to increase the driving forces, often through communication. In companies for example, the CEO will get up on his/her soapbox and explain what needs to happen and why. But according to Lewin’s theory, this will likely only result in the restraining forces increasing. Not very handy.

According to Lewin – and Kahneman – we shouldn’t ask ourselves: how do I get them to do it? But rather: why aren’t they doing it already? Kahneman: “You ask: what can I do to make it easier for that person to move?” Often, this will have something to do with removing obstacles in the physical or social environment, states Kahneman.

Many of the people I meet in my work believe in the trio of ‘knowledge – attitude – behavior’. They’re convinced that people have to think differently first, and have to want something different, before they start displaying different behavior. And it doesn’t matter whether we’re talking about quitting smoking, eating more healthily, saving more, or a new way of working. But Kahneman insists that real change can only start once you’ve admitted that this approach is generally not very effective.

So what are you waiting for?

Ben Tiggelaar
(Originally published as a column in NRC Handelsblad).