From the Rumpus, a site with varied interesting offerings:written by Katherine Sharpe, an excerpt.
Having a melancholic humor presented obvious challenges, but there were plenty who recognized that a touch of melancholy could be a good thing. Aristotle believed that from the ranks of the melancholics came society’s artists, scholars, and visionaries. If a person’s melancholic bent “is quite complete, they are very depressed,” he wrote in the Problemata,around 350 B.C. “But if they possess a mixed temperament, they are men of genius.” He concluded: “All those who have attained excellence in philosophy, in poetry, in art, and in politics had a melancholic habitus.”