GS: Could you perhaps take us back to the beginning of the concept of fanaticism and especially the significant conjunction between politics and religion? It has its origin in ancient religious cults, and then it re-emerges in the revolutionary Christian movements in the sixteenth century…
AT: It's a term that originates in ancient Rome to describe certain religious cults, linked to groups that had come to Rome from what we now would call the Middle East or Near Asia. The word fanatic comes from fanum, temple, the same root from which we get profanation, which is of course one of the things that fanatics are said to be particularly obsessed with. Recently one of the main things the Islamic State has been known for is destruction of temples, and the whole question of iconoclasm is also part of this. But fanaticism was originally intended to designate a kind of religion, a seemingly violent or uncontrolled religion of the other. There is an interesting story of false etymology as well; during the Enlightenment, a lot of thinkers presume or project into this idea of fanaticism that which has to do with fantasy, the fantastic and phantasms.
Within the Enlightenment itself, or at least within the eighteenth century's intellectual and philosophical movements that we can link to the Enlightenment, the concept of fanaticism had a whole set of contested and contradictory uses. Among these we identify a popular idea in the 2000s, formative of liberal political thought: the distinction or opposition between tolerance and fanaticism. This is of course the Enlightenment response to the menace of religious wars, and it is at the crux of Voltaire's Treatise on Tolerance, where the philosopher would be on the side of tolerance, and those who tried illegitimately to mix political action with religion would be on the side of fanaticism. Fanaticism is the source of the worst in a society: civil war.
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