Most people in the grip of depression at its ghastliest are, for whatever reason, in a state of unrealistic hopelessness, torn by exaggerated ills an… - William Styron

it has to be emphasized that if the pain were readily describable most of the countless sufferers from this ancient affliction would have been able to confidently depict for their friends and loved ones (even their physicians) some of the actual dimensions of their torment, and perhaps elicit a comprehension that has been generally lacking; such incomprehension has usually been due not to a failure of sympathy but to the basic inability of healthy people to imagine a form of torment so alien to everyday experience.

In many of Albrecht Dürer’s engravings there are harrowing depictions of his own melancholia; the manic wheeling stars of Van Gogh are the precursors of the artist’s plunge into dementia and the extinction of self. It is a suffering that often tinges the music of Beethoven, of Schumann and Mahler, and permeates the darker cantatas of Bach. The vast metaphor which most faithfully represents this fathomless ordeal, however, is that of Dante, and his all-too-familiar lines still arrest the imagination with their augury of the unknowable, the black struggle to come:

Loss in all of its manifestations is the touchstone of depression — in the progress of the disease and, most likely, in its origin.