Religion is a complex phenomenon that is both widely recognizable and extremely varied. It is a system of beliefs and practices that protects, transmits and guides people in their life project. It may do so in a narrow and focused way (the traditional definition of a religion is the belief in gods and/or judgement after death), or it may go much wider in its scope, encompassing all of the goals that people consider to be most important in life, from personal wealth to happiness to the meaning of life. Religions also differ in their ways of organizing the knowledge they hold, whether tightly focused with a central hub such as the Vatican or a clear hierarchy of priests, bishops, cardinals and laity, or more broadly by allowing a great deal of freedom for different subsystems, centered on gurus, temples and holy places.
One major issue with religion is how it organizes time, which for most religions is a central concern. In some religious traditions, such as the major Western religions, time is viewed in a cyclical manner and the hope is that life can be saved through an afterlife, whether in heaven or some other form of reward or escape from pain, as in Christianity. In other traditions, such as most Eastern religions, time is viewed in largely linear terms with lives being lived only once and then dying and being reborn and reincarnated repeatedly until the end of time, when the cosmos will come to an end.
Most attempts to analyze religion have used “monothetic” approaches, based on the classical idea that a concept can be accurately described by only one defining property that all instances of the concept share. Recently, however, there has been a move toward analyzing religion using “polythetic” approaches, in which the concept of religion is treated as a family-resemblance concept that encompasses all of the various aspects that have been found to qualify as religiosity.
The polythetic analysis of religion raises two philosophical issues that are similar to those that have arisen in the analysis of other abstract concepts for sorting cultural types, such as democracy and literature. These relate to the nature of social kinds and their emergence, and the way that one’s definition of a religion may influence the kind that it names.
It has been argued that to use the term religion in this way is to imply that it is universal, present in all human cultures. This is incorrect, because a concept can be defined functionally as referring to a certain kind of social practice without being universal in the sense that it is the same in every culture. Further, it is possible to develop a notion of the essence of a religion even without assuming that it will be the same in all cultures. Nonetheless, it is necessary to be cautious about claims that polythetic definitions of religion are flawed or that they are inherently less accurate than monothetic ones.