The counterpart of atheism in Islamic thought: Dahriyya

The concept of Dahriyya, derived from the Arabic root dahr meaning "absolute time" is used in Islamic thought to denote atheistic and materialistic tendencies. The fact that no systematic Dahriyya movement has emerged within the history of Islamic thought, such as the Mashsha'iyya movement based on Aristotelian philosophy or the Ishrāqiyyun movement based on mystical experience, makes it difficult to examine it from a historical perspective. The heretical movements that developed within Islamic history and the violent reactions they received have, in places, broadened the definitions made for the concept of Dahriyya and made its boundaries unclear. Furthermore, some non-materialist views have also been regarded as dahrî on the grounds that they were thought to lead to denial. Rather than a distinctive definition of Dahriyya in the sources, there are definitions sufficient to consider a person or a thought as dahrî. In order to eliminate this uncertainty in our study, we first addressed the concept of atheism. Subsequently, the history of atheism was examined under four headings, corresponding to the philosophical periods: Antiquity, the Middle Age, the Early Modern Age, and the Modern Age. After explaining atheism, the concepts of Dehriyye and dehrî were examined according to Islamic and Pahlavi literature. The treatment of the concept of dahrî in classical and modern sources was examined, and dahrî religious groups and sects were identified. Finally, information about the identified religious groups and sects is provided in accordance with the principles of the history of Islamic sects, and their relationship with Dahriyya is discussed.