The emergence of rationalist and traditionist approaches among Moslems was the result of attention to different verses of the Holy Quran, some denoting reasoning and some denoting devotion. These different approaches to Quran led to the formation of Mo'tazele and Asha'arites schools among the Sunnites and Osuliyyun (rationalists) and traditionists among the Shiites. This difference was the cause for many religious and socio-political conflicts.
The development of rationalism in Imamiyye started in Bagdad in the fourth century (AH) and continued up to eleventh century, dominating Qum and Ray schools of thought.
But, later, the intellectual and political changes resulted in the revival of traditionism among the Shiite scholars. And, as a result, traditionism dominated most intellectual schools in Iran, Iraq, and Bahrain in 12th century.
However, with the scientific and practical measures of Allameh Vahid Behbahani and his followers and Shaikh Morteza Ansari, rationalism dominated once more.
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