Theism has flourished in Western philosophy, thanks in part to the work of Plato (428348 bce) and Aristotle (384-322 bce). Both philosophers were theists (in the very broad sense of the term) and their massive influence on the history of ideas insured that theism would be a topic of interest for many ancient, medieval, Renaissance, and modern philosophers. Modern science did not (at least at first) diminish philosophical interest in theism, as all the great early modern scientists (Kepler (1571-1630), Newton (1643-1727), et al.) were theists. Theism played a significant role in the early modern philosophical work on skepticism (Descartes’ Meditations (1641)) and even some of the great early modern skeptics (Pierre Bayle (1647-1706)) subscribed to theism. In analytic philosophy in the twentieth and twenty-first centuries, theism has been a major recipient of positive and negative attention. While two of the gigantic founders or leaders of what has become known as analytic philosophy were skeptics, G. E. Moore (1873-1958) and Bertrand Russell (1872-1970), the methods of analytic philosophy themselves are not inimical to theism for some of the most outstanding analytic philosophers today are theists (such as Alvin Plantinga and Richard Swinburne) or sympathetic to theism (William Rowe). Significant numbers of atheist and agnostic analytic philosophers (such as Richard Gale and Michael Tooley) have also authored serious work critical of theism, thus further securing the place of theism as a topic of great interest. Theism has had an important role in Continental philosophy in the early modern era (Descartes (1596-1650), Pascal (1623-62), Leibniz (1646-1716), and Kant (1724-1804) were theists, albeit in Kant’s case, his theism was a matter of moral faith) and theists have made use of the philosophical methodologies of empiricism, rationalism, and its hybrids.