Although scholars have a range of definitions for Religion, the most commonly used today is a functional one. It treats the term as a social taxon that consists of a number of different kinds of practices that people engage in. Often, these involve belief in particular supernatural or spiritual beings or institutions. Other common features include ritual, community, and morality. The emergence of this functional approach has raised two philosophical issues for the concept of Religion.
The first issue is whether we can understand the category of Religion using the classical theory of concepts, which assumes that any given practice will have a single defining property that distinguishes it from others like it. The second issue is the extent to which a particular kind of activity should be categorized as Religion. For example, it would be a mistake to define Religion as something that is always or usually about the human need for transcendent meaning. Similarly, it would be misguided to define Religion as anything that is always or usually about the need for a certain type of social organization or institution.
These issues have prompted some social scientists to abandon substantive and functional definitions altogether in favor of what is called the Verstehen approach. It is based on the assumption that most participants in religious activities already have working definitions of their own and that a depiction of religion that fails to reflect these definitions would distort rather than report (see Runciman 1969). This approach has not become widely adopted because it requires the researcher to be present in the field and to participate in the actual religious practices being studied.