Was Uncle Arthur A Dybbuk? Did He Draw The Storm?
We see in the first scene that a Dybbuk can appear in the form of a blood relative, and that it likes to be invited into a person's home (or life). It is implied that if a dybbuk is not dealt with and driven out swiftly then it will bring misfortune on the household.
Like most people, I first saw Uncle Arthur as being nothing more than a one-dimensional background comedy character. I never expected to see him onscreen, thinking he would remain forever in the toilet.
After some depth and even anguish was introduced to his character, though, I felt a lot of sympathy for him. Now I'm starting to wonder if he was the cause of Larry's downfall. We don't know when he first moved in with the family, or why, but obviously Judith didn't immediately call him a dybbuk and kill him like the peasant woman did in the first scene. Larry stood by him despite the problems he caused as well. They were passive, whereas the woman in the first scene actively drove the dybbuk from the home.
Arthur's Mentaculus seemed almost like an occult or demonic book more than a maths formula (though advanced maths is pretty occult in and of itself). We are shown that it gives Arthur certain powers - to win at gambling, but it must surely have deeper uses and significance than that? Seems like he spent his whole life working on it.
Anyway, in the scene where Arthur complains about his life - "Hashem gave me bupkiss!" - he expresses resentment of Larry's family life and job, and even curses God. Larry, though largely secular-minded, is shocked and tells him not to talk that way - presumably because it would anger God.
Larry loses all the things that Arthur resented him having - his wife, his home, his job is placed in serious jeopardy, and at the end it seems his kids might be killed too. The doctor's phone call hints that Larry himself has a very serious illness and will probably die. Did Arthur, knowingly or not, call down this doom on his brother's head through his resentment? Was he the dybbuk who brought misfortune on the House of Gopkin?
"Dybbuk never eat."
We see Arthur leave a meal uneaten at one point (too busy in the bathroom) but we also see him drinking some kind of milk or supplement at another point, so I'm not sure. A red herring maybe.
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