Affectus and passio in the Summa theologiae of Thomas Aquinas

Thomas Aquinas is known for his treatment of the passions at Summa theologiae 1–2.22–48. The Summa also speaks of affectūs and affectiones. To what do these terms refer? How are their referents related to passiones? These questions require close attention to three cases: divine, angelic, and human. In the human case, imposing a sharp affectus/passio distinction on the Summa is a mistake. It arises, I show, from insufficient appreciation of the difference between angels and embodied intellects.