 A significant development in the late 17th century relating to the war against the perceived atheism of Hobbes, Spinoza, and their followers was the establishment of the Boyle Lectures in 1691. These lectures, founded by the distinguished scientist Robert Boyle, served the purpose of defending basic Christian theology against “notorious Infidels,” in particular atheists (see MacIntosh 2006) — a project that had considerable overlap with the project outlined half a century earlier by Descartes in the Letter of Dedication of the Meditations on First Philosophy (1641). By the early 18th century the Boyle lectures had become the focus for the debate between religious philosophers (amongst which the Newtonians emerged as particularly important and influential) and speculative atheists. The most influential of the Boyle lecturers was Samuel Clarke, who was a close friend of Newton’s and widely recognized as the most able defender of Newtonian philosophy and theology. Clarke’s Boyle lectures, published in 1704 as A Demonstration of the Being and Attributes of God, developed an elaborate version of the cosmological argument (or “argument a priori” as it was then called), an argument then very much in vogue, having been sketched in influential books like John Locke’s Essay Concerning Human Understanding (1690). Locke and Clarke took the cosmological argument to be capable of demonstrating the existence of God with mathematical certainty. Clarke’s version of this argument enjoyed considerable prestige throughout the first half of the 18th century and found strong support among several Scottish philosophers of considerable reputation at this time. In addition to the cosmological argument, the design argument was also widely endorsed by religious philosophers and scientists at this time, including Newton himself. It is these two alleged proofs for the existence of God that Hume’s philosophical writings are particularly concerned with discrediting.