It is universally acknowledged that, for St. Thomas, there is a distinction between human persons or supposits and their natures or essences. But it is usually thought that there is no parallel distinction between the angelic person or supposit and its nature. Yet, as this paper argues, Aquinas consistently puts forward just such a distinction. This paper surveys Aquinas’s arguments for the unique identity of God with his essence and the corresponding distinctions between created persons and their essences, showing in (...) the process how the distinction found in angels differs from that found in material substances. It is important to recognize the distinction between supposit and nature in angels not only for its own sake as it touches on his understanding of created persons—human or angelic—but also insofar as it sheds light on Aquinas’s understanding of divine simplicity and of other act-potency compositions in creatures. (shrink)