 (Isaac of Stella, Letter on the Soul, 1878d, trans. in McGinn 1977). Isaac’s classification was quoted in the influential twelfth-century pseudo-Augustinian treatise De spiritu et anima (782; cf. 814, trans. in McGinn 1977) and through it in Philip the Chancellor’s Summa de bono (748–749). Before Isaac, the Stoic classification of emotions and the Platonic division of the soul were presented together in William of St. Thierry’s De natura corporis et animae (trans. in McGinn 1977), without an explanation of how they are related to each other (2.88–91). Distress is an irascible emotion in Isaac’s classification, as in Avicenna, but Isaac was influenced by the Latin tradition in which concupiscible emotions are directed to good objects and irascible to harmful ones (Knuuttila 2004: 229). William of St. Thierry writes that anger and love are good irascible dispositions of a pious soul and match together because of the fervor of love and the hatred of vices. Bernard of Clairvaux similarly classified joy and anger as irascible passions. (Opera V, 358–359). For the Cistercian list of affects, see also Boquet 2005.