Philosophy of religion is "the philosophical examination of the central themes and concepts involved in religious traditions". Philosophical discussions on such topics date from ancient times, and appear in the earliest known texts concerning philosophy. The field is related to many other branches of philosophy, including metaphysics, epistemology, and ethics.
The philosophy of religion differs from religious philosophy in that it seeks to discuss questions regarding the nature of religion as a whole, rather than examining the problems brought forth by a particular belief-system. It can be carried out dispassionately by those who identify as believers or non-believers.
Philosopher William L. Rowe characterized the philosophy of religion as: "the critical examination of basic religious beliefs and concepts." Philosophy of religion covers alternative beliefs about God or gods or both, the varieties of religious experience, the interplay between science and religion, the nature and scope of good and evil, and religious treatments of birth, history, and death. The field also includes the ethical implications of religious commitments, the relation between faith, reason, experience and tradition, concepts of the miraculous, the sacred revelation, mysticism, power, and salvation.
The term philosophy of religion did not come into general use in the West until the nineteenth century, and most pre-modern and early modern philosophical works included a mixture of religious themes and non-religious philosophical questions. In Asia, examples include texts such as the Hindu Upanishads, the works of Daoism and Confucianism and Buddhist texts. Greek philosophies like Pythagoreanism and Stoicism included religious elements and theories about deities, and Medieval philosophy was strongly influenced by the big three monotheistic Abrahamic religions. In the Western world, early modern philosophers such as Thomas Hobbes, John Locke, and George Berkeley discussed religious topics alongside secular philosophical issues as well.