Over the course of the twentieth century, a great many people were liberated from accusations of laziness, of stupidity, and even of demonic possession, by such diagnoses as Depression, Dyslexia, and Dissociative fugue. It is not only distress, but also deficiency, that has a place in normal life. Deficiency should not by itself be thought to give sufficient grounds for taking some condition to be a diagnosable disorder, even if this deficiency is one that psychiatry would be equipped to alleviate. Nor is every mental disorder distressing – at least not for the person whose mental condition is disordered. The limitations of introducing this concept of malfunction to the account of disorder mark one of the ways in which psychiatry faces complications that go beyond the complications faced by other branches of medicine. Disorderly social interactions can therefore threaten the opportunities for flourishing.