As is well known, the homicide of Caliph Osman created an imminent and farreaching effect on Muslim thought. After this event one can figure out how extreme edges muslims went like Murcia and Haricis. Mu?tazila represents the middle way between these two extreme. Besides, Mu?tazilite thinkers were the representatives of free thinking in early muslim society. Among stormy philosophical speculations by outside influences, a reflexive impulse to moral issues was developed by these thinkers, which can be easily seen in their formulations of five principles. Through these principles they tried both to challenge to foreing effects such as Christianity, Gnosticism, Manichaean dualism, etc., and to develop a sui generis ethical outlook. Their approach to religion and religious thinking became a prototype in modern period especially in the sub-continent