Religion is a complex and controversial phenomenon that has inspired debate across many disciplines including (but not limited to) anthropology, sociology, history, philosophy, psychology, religious studies and cognitive science. Despite its complexity, a largely stable set of beliefs and practices has been identified that is shared among most religious groups. These beliefs and practices are codified in prayer, rituals, scriptures and religious law. The term “religion” may also be used to describe a general feeling of oneness with God and the universe.
Several different definitions of religion have been proposed, ranging from the broad to the narrow. The most common type of definition is the substantive definition, which classifies something as a religion if it involves belief in a distinctive kind of reality. This approach has been criticised as being overly broad and uncritical. For example, it would include belief in ghosts and other supernatural beings, but exclude some faith traditions that emphasize immanence or oneness, such as Buddhism and Jainism.
A more recent approach is the functional definition, which classifies a thing as a religion if it generates social cohesion or provides orientation in life. This approach has also been criticised as being too narrow.
A third approach is the polythetic definition, which classifies a thing as religion if it has multiple features that are mutually relevant. This approach has been most recently associated with the burgeoning field of the cognitive science of religion. The idea is that by identifying all the possible features of what can be called religion, one may be able to construct a definition that is more accurate and more meaningful than either stipulative or functional approaches.