I do, however, wonder why so many people experiencing melancholia are now taking pills simply to ease the pain. Of course there is a fine line between what I’m calling melancholia and what society calls depression. In my mind, what separates the two is degree of activity. Both forms are more or less chronic sadness that leads to continuing unease with how things are — persistent feelings that the world is not quite right, that it is a place of suffering, stupidity, and evil. Depression (as I see it, at least) causes apathy in the face of this unease, lethargy approaching total paralysis, an inability to feel much of anything one way or another. In contrast, melancholia generates a deep feeling in regard to this same anxiety, a turbulence of heart that results in an active questioning of the status quo, a perpetual longing to create new ways of being and seeing.
[snip]
Melancholia, far from a mere disease or weakness of will, is an almost miraculous invitation to transcend the banal status quo and imagine the untapped possibilities for existence. Without melancholia, the earth would likely freeze over into a fixed state, as predictable as metal. Only with the help of constant sorrow can this dying world be changed, enlivened, pushed to the new.
Poets are friends with melancholy. All artists are. Probably scientists as well.