Religion is a complex phenomenon that spans cultures and time. It is commonly understood that religions appear in all human societies and that they share certain common features that distinguish them from other social phenomena. These shared features are sometimes referred to as the “genus” of religion (see the article on Definitions of Religion for an explanation). Various functional approaches define religion by referring to beliefs and practices that generate social cohesion or provide orientation in life. The most widely used of these is Emile Durkheim’s concept of religion as a unified system of beliefs and practices relative to sacred things that unite people into a moral community. Other scholars reject functional approaches that treat religion as inevitable features of the human condition and instead focus on the structure/agency debate and the concept of valuation.
Substantive definitions of religion emphasize the way people deal with ultimate concerns like their lives after death and their fate in the world to come. These typically rely on the belief in supernatural beings and include concepts like ghosts, angels, spirits, demons, and gods. Critics argue that this definition is too broad and fails to consider nontheistic faith traditions, such as Jainism, Buddhism, and Daoism.
Monothetic approaches define a class by proposing a single property, or set of properties, that is necessary and sufficient for membership in the class. Most definitions of the term religion have been of this type. These stipulative definitions, however, do not make it possible to critique the terms on which they are based and can result in problematic assumptions about the nature of religion. A polythetic approach, on the other hand, allows for the discovery of patterns in the co-appearance of properties that may provide explanatory insights.