ABSTRACT
This chapter addresses how Augustine, Anselm, and Aquinas (AAA) understand the doctrine of original sin. Original sin is a disorder or infection affecting all of humanity such that we all tend towards doing evil. It stems from the first sin of the first people, Adam and Eve. This introduces two related problems: Why does God permit evil choices? And what sort of free will do human beings have? AAA agree that God permits evil choices because of the value of free will and in order to bring good out of them. But, regarding the nature of free will, Augustine and Aquinas are compatibilists while Anselm is a libertarian. Thus they propose different causal explanations for the Fall of Adam and Eve. The transmission of original sin introduces a new problem. Augustine sees original sin as a stain, while Anselm sees it as an absence. Aquinas seems to adopt both approaches and also to emphasize the damage original sin does to human nature.
