Warning: SPOILERS for Joker.

Arthur Fleck (Joaquin Phoenix) in Joker may not have a soul if fans of The Simpsons judge the character by one of the series' most beloved episodes, "Bart Sells His Soul". In one of Joker's few attempts at humor, Arthur has a pratfall where he walks into an automatic sliding door, which harkens back to a similar moment in "Bart Sells His Soul". In Joker, director Todd Phillips' intense and disturbing character study explores Arthur Fleck's descent into madness but there are existential questions at work here as well and one is reminiscent of the crisis Bart Simpson faced after selling his soul.

Arthur's gradual transformation into the insane murder clown coincides with the groundswell of anger from the poor and disenfranchised people of Gotham against the city's elite, personified by the crusading mayoral candidate, billionaire Thomas Wayne (Brett Cullin). The incident that sparked Gotham's violent "Kill the Rich" movement was Arthur killing three Wayne Finance stockbrokers in a subway, which turned the "Clown Vigilante" into a hero to the lower classes. For Arthur, the public support for the Clown Vigilante was recognition he pines for; as he tells his social worker Debra Kane (Sharon Washington), Fleck now feels like he actually "exists" after feeling the opposite his whole life. Later, when Arthur is confronted by two police detectives outside of a hospital as a suspect in the subway murders, Fleck walks into a sliding glass door - a physical gag identical to when Bart Simpson (sans his soul) did the same in "Bart Sells His Soul".

Related: Why Joker's Critic Reviews Are So Divided

The joke when Arthur smashed his face into the automatic door is that he didn't realize it was the "Exit"; he even waved at the sensor and it didn't register him there. The gag is eerily and hilariously similar to what happened to Bart after he sold his soul to Milhouse for $5: the Simpson family's proud underachiever quickly discovered sensors for automatic doors no longer detect him, nor does Bart have the breath to fog up a glass window, prompting Nelson to mock him with the immortal putdown, "Way to breathe, no-breath!" Bart's existential meltdown continued until, through suffering and prayer (and Lisa buying her brother's soul back from Milhouse), Bart earned his soul back and he promptly swallowed the piece of paper containing his soul for good measure. But the flip side is that while Bart Simpson's soul was restored by the end of the episode, Arthur Fleck completely lost his in Joker.

Whether or not this is all just sheer coincidence, there are more amusing (unintended) similarities between Joker and "Bart Sells His Soul": Bart's mother Marge noticed her "special little guy" was "missing something" and assured him that he's "not a monster", much like how Arthur's elderly mother Penny Fleck (Frances Conroy) always tried to see the best in her son, whom she nicknamed "Happy". And, like Bart's nightmare about everyone else in Springfield cavorting with their souls except for him, whole swaths of Joker were Arthur's delusions of events that didn't really happen.

The classic Simpsons episode and Joker also each addressed whether the soul is linked to having a sense of humor: when Bart lost his soul he no longer found Itchy & Scratchy funny and he couldn't even muster a chuckle when Homer pratfalls and Santa's Little Helper starts chewing on his behind. In Joker, Arthur Fleck yearns to be a standup comic but he has no understanding of humor and his disturbing comedy act completely bombs; Arthur simply lacks the capacity to subjectively comprehend what's actually funny and perhaps it's because Fleck simply has no soul. As Arthur embraces his lunacy and fully becomes the Joker, his soullessness is evident in the gruesome murders he gleefully commits by Joker's ending.

Perhaps it's Bart's soul that ultimately keeps him from the path of darkness. Meanwhile, despite his serious laughing mental illness, the Joker just isn't funny (and never could be) because of what Lisa meant when she quoted Chilean poet Pablo Neruda: "Laughter is the language of the soul". Arthur Fleck may have had a soul once but, by the end of Joker, his soul is lost for good. And, it's also safe to guess that, unlike what Bart Simpson claimed, Joker is not familiar with the works of Pablo Neruda.

Next: Our 11 Biggest Unanswered Questions After Joker

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