Religion is a fundamental part of the lives of two-thirds of the world’s population. It is important for people because it has positive effects on their health, education, economic well-being, and social behavior and values. It can reduce the incidence of social pathologies such as out-of-wedlock births, delinquency, alcohol and drug addiction, homicide, mental illness, health problems, and prejudice. It also increases social cohesion, trust, and altruism. In addition, practicing religion teaches people to be responsible citizens and good parents and children. But if it is not understood and appreciated, religion can create conflict and lead to problems for individuals and society.
There are many approaches to defining religion, both substantively and functionally. Substantive definitions of religion often include belief in a supernatural being or realm, morality, and participation in religious rituals. However, these definitions are often too broad and include beliefs in disembodied spirits, and may exclude faith traditions that emphasize immanence or oneness, such as Buddhism, Jainism, and Daoism. Furthermore, they are ethnocentric.
In contrast, functional definitions of religion seek to understand the functions that it serves for its adherents. They can be traced back to Emile Durkheim (see Durkheim, Emile ), who developed an account of religion as a unified system of beliefs and practices that reinforce social solidarity in a group. A more general functional approach was taken by the sociologist Rodney Needham who, using a computer program to sort bacteria, found that certain properties co-appear in groups of organisms and could serve as criteria for classifying them.