David Hume (1711–76) was a best-selling historian, essayist, polymath, and enormously influential and important philosopher of the eighteenth-century Scottish Enlightenment. He was both a philosophical radical and a political moderate. Hume was intellectually skeptical, particularly about the scope and power of reason and supernatural beliefs (such as the existence of God) and averse to the airy sciences of traditional metaphysics, preferring to restrict himself to fact, experience, and observation, often with devastating effects. He had a very keen awareness of the strange infirmities of human understanding, which disposed him toward doubt and epistemological caution. Politically, he was essentially a pragmatist who eschewed strongly ideological positions. Hume was born in Edinburgh to a respectable, moderately prosperous family whose home (Ninewells) was in the lowland Borders region of Scotland where he grew up. At a precociously young age, ten or twelve, he started studying law at…