The expression “Arab reason” is quite multifaceted: it poses different problems at the same time: the problem of reason as such and its connection with the Arab language and Arab culture. In order to understand the complexity of the task or at least part of it we need to immerse ourselves in different layers of culture: in religion of Islam, theology, science of law, philosophy, poetry and folklore. Historical and cultural view on the “reason” makes it possible to highlight its epistemological aspects, its ambiguity and even plurality of the familiar phenomenon of “reason”. The perspective on the “reason” in close connection with the changes happening in Arab culture and nations that entered the Caliphate allows you to see its preserved connection with the pre-islamic worldview. It allows you to see remnants of consciousness of the “jahiliyya” era and the emergence of new forms of perception, understanding of the world, such as the “science of faith”, logic, philosophy, natural sciences and society.