Political extremism is a complex and difficult subject. Indeed, the very concept “extremist” sometimes makes people uncomfortable. Is not extremism always relative to some set of values, whose rightness is open to debate? As citizens of democratic countries, we often find extremism inside our polities distressing. On the other hand, when extremism occurs in non-democratic settings it often appears to many of us as liberating. Thus, we are often forced to distinguish between the “decent” extremism of those “fighting for political liberation” and the “indecent political brutality” of domestic extremists. And even when we are sympathetic to the aims of the latter, we are often led to wonder why human rationality is unable to eliminate the social waste implicit in the violence and disruption often associated with extremist activities.

As is widely acknowledged, we owe our political liberties today to some extremists of the past and too much conformity is a danger to our intellectual life and to social progress. At the same time, the conformity often observed within extremist movements is sometimes even more remarkable and disconcerting than the conformity within the wider society to which such movements sometimes set themselves up in opposition. Thus, another contraposition is that, in some ways, extremism and conformity are opposites; in other ways they are simply different aspects of the same phenomenon.