An Analysis of the Roots and Historical Developments of the Multiplex Consensus

Multiplex consensus is one of the reasons that is widely used in fiqh and usul-i fiqh. In this kind of consensus that is employed - after its definition - for negation of the opinions about a question, the argument is based on the existence of two or more viewpoints about the same question. Multiplex consensus, while being prevalent, none of its bases and rules have been properly discussed and its roots and evolutions have not yet been studied. This type of consensus that takes different forms like third viewpoint rejection and lack of dissociation viewpoint, in spite of its definition, is mostly used to generalize the rules and not to negate them. The topics of this discussion have been born and flourished in Sunni usul-i fiqh books particularly the books written in theologians’ tradition and from the fourth century onwards, it has been used in fiqh and usul-i fiqh. Shi’ites also have integrated this question with special Shi’ite viewpoint in usul-i fiqh books and used it in fiqh and usul-i fiqh arguments.