Hassan Yussefian and Ahmad Hussein Sharifi
The term “reason” (‘aql) has been used in various senses in philosophy and other disciplines; and in its most popular sense, it is a power specific to man by which he distinguishes good from evil, and tells the path from the river. Mulla Sadra (979-1050 AH Lunar) enlists six meanings for the term “reason” and thinks of usages of the term in these meanings as some sort of polysemy. If we take into account the usages of the term in western culture as well, its meanings will increase in number; for example, today, terms such as instrumental rationality are used in particular in sociological discussions and means that we have to choose the best instrument to attain our goals. Evidently, this is of a pragmatist aspect; while concerning the issue of reason and revelation, we evaluate reason’s abilities and inabilities in the realm of religion through an epistemological approach.
Reason and revelation two sources of knowledge for man; their difference, however, is that one of them is open to all and the other is specific to a small group. Thus, first of all, we throw a glance on various ways to acquire knowledge, and divide them into public and special ones; and in this way, we clarify two terms “reason” and “revelation”.
 . See, Mulla Sadra, Sharh al-usul al-kafi, vol. 1, pp. 227-222
 . See, Soroush, Abdolkarim, Lessons in the Philosophy of Sociology, p. 211