In my essay, “The Genesis of St. Augustine's Idea of Original Sin,” published in this Review (1917, pp. 159–175), I advanced the theory that Augustine's doctrine of original sin and its transmission was not derived from the teaching of Ambrose, as Harnack holds, but rather from the commentary on the Epistle to the Romans by the unknown writer commonly referred to as Ambrosiaster. From this fourth-century writer Augustine borrowed his final formulation of the doctrine of the universal participation of mankind in the sin of Adam and his interpretation of the most discussed passages of the Epistle to the Romans, as well as the notions of man “servus culpae” and “servus gratiae.”