From Jesus Christ to Salman Rushdie, from Moses to Freud, blasphemy has been a force in producing many forms of Western cultural identity. Blasphemy continues to influence our relations with other cultures, yet it is not so much an idea as a shifting rhetorical figure. It stands for whatever we deplore: we define the truths we uphold in terms of the blasphemies we attack. "Blasphemy is an orthodoxy's way of demonizing difference," writes...