Religion is a complex and varied subject. Some scholars use the term to refer to a belief in a specific kind of reality; others consider it to include a set of social practices, such as rituals or traditions and their accompanying beliefs and values; still others treat religion as a set of practices that are characterized by some sort of societal organization, whether or not they involve belief in a particular supernatural entity.
In the past, most academics took a “substantive” approach to religion, which determined membership in a religious category by virtue of believing in an unusual kind of reality. However, since the twentieth century, a newer and more productive way of thinking about religion has emerged, as seen in Emile Durkheim’s definition of religion as whatever system of practices unites people into a moral community (whether or not those practices involve belief in supernatural realities) or Paul Tillich’s definition of religion as whatever dominant concern organizes a person’s values.
Anthropologists have long studied the religious life of tribal and “primitive” societies, and it was natural for them to try to use that experience in their speculation about the genesis and function of religion. In fact, it has even been possible to find evidence for a religion-like activity among prehistoric humans: paleontologists and archaeologists have discovered burial rituals in the remains of Neanderthals and other extinct subspecies of human being. Nonetheless, attempts to define a religion based on contemporary nonliterate societies were never very successful, and in the last several decades, scholars have dropped the search for a substantive definition in favor of a more functional one.