I think expressionism is a little misunderstood.
Freud, too, maybe.
But there is so much projected darkness and miserable feeling, and most of all a stated relationship between Madness and Fear…nearly as polar caps in a very dark, watery, earth.
Rather I would like to express (!) that this may come from a much more middle place.
Possibly, less honest, but more aesthetically driven.
What expressionism is not:
Lethargic (my biggest point, here!)
Cheap (aka, the twilight series “darkness”, or music like Evanescence the band)
What expressionism IS:
focus on blurriness
focus on darkness, night
focus on the mind/thought
focus on perception
an interest in the feeling of something rather than the something
a transference of excitement in darkness
Archetypically, Professional thieves live their lives and perform their jobs in the night, in a hiding, natural cover. Their job allows them to perform something very risky over and over: their potential for mistake is fatal, yet hardly possible to actually achieve! Their jobs mean punishment and death, near the end. But for this kind of brooding future, they are given repeated excitement about the job, each time. The impending death hangs over their head, making each moment filled with some equal amounts of fear and thrill.
I do not think anyone would assume one of these thieves is an evil person without knowing them, so we can throw the assumption that these people are crazy, bitter, or just plain facetious. Yet, they prefer to hold no innocence, yet in lieu of purity they gain an everyday life that is more worth living, in a way.
They are guilty, and this acceptation of sin allows life.
Expressionism is exploring this thought in the mind of a thief, allowing the darkness to become the source of excitement and energy! Its sensuousness performed in life. Opulence of evils, decadence of night.
Pierrot Lunaire, by Arnold Schoenberg, in my opinion is the epitome of this attitude in art. Darkness of ancient and modern ideas are all converged under one moon, in the form on one man with many dualities. The instruments are in constant elusion with each other in a conversational way. The dark music of cabaret is thrown into the world, much like the film Moulin Rouge, as a basis of working, as an everyday evil that is just a venue for excitement. Here, we have the moon, and the moon holds us in conversation with our most grotesque ideas and we feel no shame, hate, lethargy, but are filled with electric energy, and merciless excitement. Ah!