Religion is one of the most ancient and diverse human creations. Its many different forms have been the source of enduring art, music, dance, and drama. They have also been the resource for explorations of the cosmos that issued into what we now call the natural sciences. And they have been sources of inspiration for many of the most prestigious intellectual achievements in history, from architecture and philosophy to astronomy and mathematics.
Today, the concept of religion has become a taxon for social formations, the sort of category-concept that includes such things as Judaism, Christianity, Islam, Hinduism, and Buddhism. But there are two philosophical issues that arise for this contested concept, ones that probably apply to other abstract concepts used to sort cultural types.
One issue is the problem of identifying what actually counts as a religion. The classic definition offered by Edward Tylor is that religion involves beliefs in spiritual beings, and Paul Tillich offers the idea that a religion is something that deals with people’s ultimate concerns. These are single-criterion monothetic definitions, and they tend to obscure the fact that many religions incorporate many features.
The second issue is the question of how a religion translates its story into life. This is most easily done through ritual, but there are many other ways. For example, some religions have turned their attention inward and have explored such ideas as enlightenment, peace, emptiness (i.e., sunyata in Buddhism), and buddha-nature. These are called inversive systems, and they have given rise to religions like Jainism and Buddhism.