Religion is a broad topic that has implications in all sorts of fields, including anthropology, history, philosophy, sociology, and psychology. This makes it an extremely important subject of study. However, the field has been plagued by disagreements over how to define religion. The main controversy centers around the distinction between substantive and functional definitions of religion. Substantive definitions are based on beliefs in unusual realities, while functional definitions focus on the role that religion plays in life. The debate over these definitions cuts across disciplines, with the concept of religion attracting interest from anthropology, philosophy, history, and politics as well as the social sciences and even cognitive science.
Anthropologists and historians suggest that religion developed as a way for humans to cope with the inevitability of death. Religious people find comfort in the idea that there is an afterlife and that their lives have meaning. In addition, most religions have tight-knit social groups that help their members deal with stressful events.
Psychologists and neuroscientists believe that religion fulfills emotional and psychological needs in the human brain, such as a fear of death or a need for a sense of spirituality. Scientists also believe that there is a genetic component to religion, with people passing on their religious beliefs to their children.
A new school of thought, called polythetic definitions, argues that there is no one characteristic common to all religions, but that different religious systems have a similar structure. This includes rituals, sacred writings, and a belief that life is meaningful.