 Works of ancient philosophy are focused more on the psyche’s health (or eudaimonia) than its illness. Nonetheless, there are hints that just as a unified soul is one that is healthy (as well as rational and virtuous), a soul lacking unity will be disturbed, or mad. Offering an account of the harmonious soul, whose rational and non-rational elements achieve a unified whole, Aristotle leaves us a picture of the warring and fractured state of an unhealthy soul, for  example.[4]  The emphasis on disunity is here tied to the vices and irrationality: a fully unified soul is virtuous and rational, a dis-unified one vicious and irrational in its unhealthy divisions. And, while they adhere to a different account of the passions and a more knowledge-based and Platonic analysis of vice, this link with the vices and virtues is also characteristic of the subsequent Stoic analyses (Irwin 2013). A conception of mental illness as psychic disunity (as well as an association between health, rationality and virtue) reoccurs in later philosophy (Spinoza, for example), and in psychoanalytic traditions. Within present-day disorder descriptions, some symptom clusters readily fit the classical emphasis on disunity (addictions, and bipolarity, for example); others, including most personality disorders, are less persuasively depicted in such terms (see Worrell &amp; Denham 2016).