Abstract
This paper intends to show that Aquinas gives a non-deterministic account of free decision. Angelic sin is the eminent test case: ex hypothesi, angels are supremely intelligent and not subject to ignorance, passions, or negatively disposing habits. Nothing predetermines their choice; rather it ultimately depends on their freedom alone. All angels acted based upon reasons, but why certain angels acted for an inadequate reason whereas others for an adequate reason cannot be fully explained. Thomas's action theory allows him to explain angelic choice as contingent and selfdetermined. The salient features of this explanation are transferable to human free decision.
© Walter de Gruyter