The problem of defining religion and the meaning of Aqalli (minimal) and Aksari (maximal) in religion

What is religion? This question can be answered from two approaches; intra-religious approach and extra-religious approach. First view defines a true religion based on an intra-religious criterion which such definition does not include everyone. However, based on second approach, the definition of religion should be universal and proper, and an all-inclusive definition. Since it is difficult to find something common to all religions, some have benefited from family resemblance to define religion which such definition is not an all-inclusive definition. The aim of this article is to prove that a conceptual definition of religion is possible not a substantive one. Since the religion is in opposite of atheism, so with an intra-religious definition, religion can be defined as "belief in a better world" or according to the Quran as" belief in world of Unseen ". Since existing religion's modus are unique and confined to their kinds; for example, Islam can be defined according to the theological definition as "God's plan for man's salvation." The relationship between these two definitions is such as the relationship between minimal and maximal or the relationship between imperfect right and perfect right.