Anti-Islam polemics made identical Christian behavior an exception and Muslim behavior a doctrinal proof

Evidence

The Christian canon of Muslim behaviour, that is, the received Christian opinion as to what Muslims actually did, was partly formed by the tendency of misconceptions to snowball, and to confirm as well as to add to one another. Mere repetition is enough to bring unshakable conviction; and once it had been asserted that Islamic teaching was sexually lax, every example of laxity would be noticed from that moment, and, once notified, attributed to the doctrine. … If we suppose that there were an equal number of similar offences committed by Christians and by Muslims in any given time, in the former case they would be seen as having occurred in spite of doctrine, so that each individual case would be an exception, and in the latter it would be assumed that doctrine was the cause of whatever happened. Moreover, if it were not a matter of seeking examples to prove a thesis, each particular episode would be less likely to be noticed in the first place. … More often the polemic purpose guided the selection of facts, and there were few cases indeed where mistakes were made that showed Islam in a less disadvantageous light than was necessary. — Norman Daniel, Islam and the West, 1362

Categorization

• XREF: This asymmetrical hermeneutic — identical acts read as exception for Christians, doctrinal essence for Muslims — is exactly the mechanism Aziz and Razack describe for modern racialization of Muslims; a medieval forebear worth citing.
• SEED: The ‘exception vs. essence’ double-standard as a centuries-deep tool of othering: a genealogy piece tracing it from this 13th-century polemic logic through Orientalism to contemporary terrorism coverage.