 If a perfectly good and all-powerful God alone created everything in the universe, then why do pain, moral wickedness, and so many varieties of imperfection exist? Philosophers today refer to the family of issues raised by this question as “the problem of evil.” There is perhaps no thesis for which Bayle is more well-known than the skeptical claim that there is no rational solution to the problem of evil. Such skepticism can already be found in Bayle’s earliest work, the 1675–77 Philosophy Course, in which Bayle argues that no available account of God’s causal relation to sin and suffering answers the problem. Bayle again attacks theodicy (i.e. the attempt to answer the problem of evil), especially the Cartesian strand, in his 1679 Objectiones to Pierre Poiret’s Cogitationes Rationales de Deo, Animo, et Malo. And both the 1682 Pensées diverses and 1686–88 Commentaire philosophique, though they primarily deal with superstition and toleration respectively, also positively engage God’s causal role in evil and demonstrate the insoluble puzzles it raises.