 The Leibnizian-Wolffian School. As noted above, Kant had already developed some criticisms of Leibniz’s Theodicy (1710) in 1753. He also studied the works of Wolff—most notably the two-volume Natural Theology (1736–1737)—as well as the theological writings of most of Wolff’s many followers. The most important of these latter are Alexander Gottlieb Baumgarten (1714–1762) and Johann August Eberhard (1739–1809). Kant used Baumgarten’s Metaphysics (1739) in his courses on metaphysics for over forty years, and late in his career adopted its section on natural theology alongside Eberhard’s Preparation for Natural Theology (1781) for his lectures on philosophical theology. Although there are many differences, sometimes major, between these figures, they all agree generally in maintaining that the Principle of Non-Contradiction is the first principle of metaphysics, that human actions are free but still subject to the Principle of Sufficient Reason, that truths in the divine intellect place limits on the divine will, and that physical and moral laws are dependent on divine choice but can also be known as necessary from nature alone. They also all defend some version of the Ontological Argument.