 Concerning the demonstration of God’s existence, Wolff had offered criticisms (much to the chagrin of his Pietist opponents) of a variety of traditional proofs early in his career (cf. Theis 2018: 221–3). In his Natural Theology, however, Wolff presents and defends two proofs: an a posteriori proof presented at the outset of the first volume, and an a priori proof provided at the beginning of the second. Wolff’s a posteriori proof sets out from the fact (elaborated at the outset of empirical psychology) that we exist, and proceeds to argue that the reason for our existence must be found in a necessary being: