a post-formative stage of an attitudinal normalization of the principle of agreeing to disagree

The Balkans-to-Bengal complex constitutes what we might usefully conceive of as a post-formative stage and condition in the history of societies of Muslims—a stage at which earlier foundational elements are brought together in a capacious and productive historical synthesis that, in turn, provides a maniplex yet stable ingrediential base for a further striking forth in a dynamic variety of trajectories of being Muslim. By the thirteenth century (seventh century of Islamic history), the major theological points of dispute which had riven the community of Muslims in its first centuries were for the most part settled, with the theological schools—primarily (in terms of demographics) the Ashʿarīs and Mātūrīdīs—agreeing to disagree over an agreed set of secondary theological questions. [183]  Similarly, beginning from the thirteenth century, the mutual recognition by the scholars of the four Sunnī legal schools of the orthodoxy of each other’s legal method and corpus of legal positions—that is, the acceptance by members of one legal school of the validity of the legal position of another school even when one position directly contradicts the other—exemplifies a larger attitudinal normalization  of the principle of agreeing to disagree. [184]

-Shahab Ahmed, What is Islam? The Importance of Being Islamic. (Princeton and Oxford: Princeton UP, 2015, 75-76.