Study showing how people react to personal uncertainty by going to personal extremes (hardening of attitudes about social issues and groups).
Summary
This interesting research does not directly tackle extremism, but, as the authors show it does help explain how people might come to hold more extreme ideas. Their main hypothesis is that when people are threatened with personal uncertainty, they seek to remedy this by emphasising increased certainty and conviction about unrelated attitudes, values and identifications. This might help mask the inner uncertainty and as the authors note a seemingly defensive way about this might be to become more extreme about social attitudes and groups.
The data is gathered through four studies and the article sets out their methodology and the findings of each study to show subtly different ways in which people mask uncertainty with certainty (which also included constructing more consistent personal identities), and also how they might be helped to retreat from these defensive positions.