There is a school of thought that groups often bring out the worst in humankind. Think only of the Charles Mackay book on “Extraordinary Popular Delusions and the Madness of Crowds,” the U.S. Founding fathers’ visceral fear of ‘mob rule,’ or the influential social science of Gustave Le Bon and others during the French Third Republic.

And yet, as a university student future social psychologist Stephen Reicher often witnessed sublime behavior from collections of people. He saw that groups could foster racism – and they could foster civil rights movements. What he saw much of the time was group behavior “completely at odds with the psychology I was learning.”

“In a sense, you could summarize the literature: ‘Groups are bad for you, groups take moral individuals and they turn them into immoral idiots.’

“I have been trying to contest that notion,” he tells interview David Edmonds in this Social Science Bites podcast, “[and] also to explain how that notion comes about.”

In a longer-than-normal podcast, Reicher explains how group mentality can bring out the best in individuals and reviews the history of crowd psychology and some of its fascinating findings that have enormous policy implications in a world of mass protest and terroristic threat.

For example, in discussing studies on the escalation of violence, Reicher explains how indiscriminate responses by authorities can create violence rather than defuse it, a useful lesson for Western countries dealing with generally peaceful populations that may still produce a few terrorist inductees from their ranks.

Reicher is the Wardlaw professor at the School of Psychology and Neuroscience at the University of St. Andrews. A fellow of the British Academy, his most widespread recognition outside the academy comes from his work with Alexander Haslam on the BBC Prison Study, or The Experiment. He is also the co-author of several books, including 2001’s Self and Nation: Categorization, Contestation and Mobilization, with Nick Hopkins, and 2014’s Psychology of Leadership with Haslam.