Religion involves beliefs, phenomena, and practices that are regarded as sacred and that give meaning to people’s lives. Its significance and the ways that it is interpreted by people are of fundamental interest to philosophy, but it also has implications for such diverse areas as epistemology, social and political theory, value theory (including moral theory), science, art, history, and biology.
Philosophical work in religion has emphasized two broad approaches to the definition of religion. Some philosophers have favored monothetic definitions, which fasten on a single property that is believed to be the essence of religion. Others have favored polythetic definitions, which recognize many properties that are found in religions or that are typical of them without identifying any one as the essence of religion. This approach avoids the claim that an evolving social category has an ahistorical essence, which is sometimes criticized as ethnocentric.
Emile Durkheim, for example, insisted that religious beliefs and practices serve the function of creating social solidarity. Similarly, Paul Tillich defined religion as whatever a person’s ultimate concern is and serves the function of providing orientation in life. These are examples of what are sometimes called single criterion monothetic definitions. However, some scholars have shifted from these functional and monistic interpretations of the nature of religion to more realist views that treat the notion as a kind of social genus, namely, as something that appears in every culture. It is this view that has generated the popular slogan that there is “no such thing as religion.” This position, however, has its critics who argue that the use of this concept reflects and reinforces the power structures of Western colonialism.