I live with the people I create and it has always made my essential loneliness less keen

Anne-Louis Girodet de Roucy, Le sommeil d'Endymion, 1791.

Neurosyphilis is an interesting neuropsychiatric disorder that oVered a potpourri of images and therapies. So varied were its presentations that clinicians dubbed it the ‘‘great imitator.’’ Descriptions filled volumes, but once the common cause was identified and a laboratory test developed, the variations assumed less significance.

An eVective treatment gave descriptive syphilology the coup de graˆce. The classification of mood disorders presents the same dilemma. Which disorders of mood are expressions of a common pathology and which are not? How many pathopathologies are represented in the mood disorders? How many disorders are derived from one cause? Acknowledging our limited understanding of human neurobiology, is it prudent to support the many disorders of mood characterized in the Diagnostic and Statistical Manual (DSM) classification or is it better to seek a simpler basis?

For a medical classification to be useful it should be precise in its criteria of diVerentiation, predict the probable course of an illness, and guide the selection of the most optimal intervention. It should also oVer the scientist a lodestone for the selection of homogeneous populations for research study.

The psychiatric classifications embodied in DSM-IV and the 10th International Classfication of Diseases (ICD-10) are not precise, and do not predict the course of illness nor eVectively guide intervention. A simplified classification of depressive mood disorders under the rubric of ‘‘melancholia’’ achieves these aims better.

‘‘Melancholia’’ is recognized as a syndrome of gloom, apprehension, inhibited motor activity, slowed thoughts, homeostatic distress, and psychosis. Clinical criteria of the disorder are definable, laboratory tests oVer support, and course of illness is predictable with the available therapeutic options. The burden of this report is to establish melancholia as a definable syndrome in psychiatric classification.