To Become an Extremist, Hang around with People You Agree with

"People tend to respond to the arguments made by other people - and the pool of arguments, in a group with a predisposition in a particular direction, will inevitably be skewed in the direction of the original predisposition."

Published in The Spectator, this edited extract from Cass R. Sunstein's Going to Extremes: How Like Minds Unite and Divide (Oxford University Press, July 2009), unveils his theory of "group polarisation" and explains why, when like-minded people spend time with each other, their views become not only more confident but more extreme. His central thesis points to the impact of information in group dynamics.

Sunstein highlights what he calls "a general fact of social life: much of the time groups of people end up thinking and doing things that group members would never think or do on their own. This is true for groups of teenagers, who are willing to run risks that individuals would avoid. It is certainly true for those prone to violence, including terrorists and those who commit genocide. It is true for investors and corporate executives. It is true for government officials, neighbourhood groups, social reformers, political protestors, police officers, student organisations, labour unions and juries. Some of the best and worst developments in social life are a product of group dynamics, in which members of organisations, both small and large, move one another in new directions."

When such groups include authorities who tell group members what to do, or who put them into certain social roles, Sunstein argues, unjustified political extremism - which he deems a threat to security, peace, economic development, and so on - can result.

He supports his position by observing that an extremist group or a cult of any kind separates its members - physically or psychologically - from the rest of society. "With such separation, the information and views of those outside the group can be discredited, and hence nothing will disturb the process of polarisation as group members continue to talk." Sunstein then asks, "So why do like-minded people go to extremes? The most important reason for group polarisation, which is key to extremism in all its forms, involves the exchange of new information. Group polarisation often occurs because people are telling one another what they know, and what they know is skewed in a predictable direction. When they listen to each other, they move."

Sunstein provides several examples to illustrate this process; amongst them is the following: "Suppose that a group of four people is inclined to distrust the intentions of the United States with respect to foreign aid. Seeing their tentative view confirmed by three others, each member is likely to feel vindicated, to hold their view more confidently, and to move in a more extreme direction. At the same time, the very same internal movements are also occurring in other people (from corroboration to more confidence, and from more confidence to more extremism). But those movements will not be highly visible to each participant. It will simply appear as if others 'really' hold their views without hesitation. As a result, our little group might conclude, after a day's discussion, that the intentions of the United States, with respect to foreign aid, cannot be trusted at all."

The article concludes by exploring the power of social networks, on the internet and in ordinary life, to operate both for positive social change but also, on the other side, "as polarisation machines because they help to confirm and thus amplify people's antecedent views." Sunstein points, for instance, to the fuelling of Islamic terrorism by spontaneous social networks, in which like-minded people discuss grievances with potentially violent results. The major force, according to Sunstein, is not websites, which people read passively; it consists, rather, of listservs (which enable group emails), blogs, and discussion forums - "which are crucial in the process of radicalisation."