In a famous hadith, the Prophet Muhammad told his followers, “Be different!” He also warned them about the potential dangers of imitating non-Muslim communities. Over the next fourteen centuries, various Muslim scholars pondered and elaborated the possible meanings of this prophetic advice. In what ways should Muslims be different? Were all forms of imitation bad, or were the good and bad forms of imitation? How much did social and political circumstances affect whether a Muslim should visibly mark his or her difference from non-Muslims around them? And so, long before Western societies began theorizing ‘assimilation’ and ‘diversity,’ Muslim scholars were writing multi-volume studies devoted to the question of what it meant to live in a multiethnic and multireligious society. Nile Green talks to Youshaa Patel, author of The Muslim Difference: Defining the Line between Believers and Unbelievers from Early Islam to the Present (Yale, 2023).