Kalām (Arab.; literally “word,” “utterance,” “speech”) denotes a theological system in Islam, in which the question of the relationship between revelation and reason is central. It developed in the early expansion phase of Islam through cultural contact with non-Muslim transmitters of ancient philosophy and sciences. In the 9th and 10th centuries, kalām influenced the theological thought of Jews in Islamic dominions. Kalām gained lasting popularity among the Karaites in particular; by contrast, its r…