In the study of sectarianism and the history of Islamic thought, the concept of "nahla" (intellectual/religious school) is fraught with definitional ambiguities and contradictory applications in both classical and contemporary texts. The inadequacy in the historical understanding of this concept, which plays a pivotal role in analyzing intellectual and religious currents, has led to fragmented interpretations of the evolution of religious and philosophical concepts within Islamic civilization.



This research employs a historical-semantic approach, utilizing lexical analysis and examining the historical context of the term in primary heresiographical sources (such as the works of al-Shahrastani, Ibn Hazm, al-Mas'udi, al-Isfarayini, and others), as well as contemporary Arabic, Persian, and Western scholarship. It aims to elucidate the trajectory of semantic evolution of the concept of "nahla" in classical Islamic texts and modern studies, seeking to answer the central question: How has the meaning of the concept of "nahla" transformed in Islamic sources and contemporary studies?



The findings of the research indicate that although the criteria for identifying a "nahla"—such as the absence of a divine law (shari'a) according to al-Shahrastani, the denial of monotheism according to al-Malati, or a hidden agenda to invalidate religion according to al-Razi—differ among authors, they all concur in placing it in an identity-based opposition to the "unified community" (umma wahida) or "true Islam." In contemporary studies, this concept is also generally used with the same negative connotation, equated with deviant or heterodox schools of thought.