confesses that she will be lost without him. Mr. Bergstrom replies that the life of a substitute teacher is transient, and he has to help the more needy. He writes her a note and tells her that any time she feels alone, its contents are all she needs to know. He boards the train and departs. The note reads, "You are Lisa Simpson." Meanwhile, Bart's class prepares to elect a class president. Mrs. Krabappel nominates Martin, while Sherri and Terri nominate Bart. During a debate with Martin, Bart tells jokes and wins the class over. Certain of Bart's victory, Bart holds a premature victory party during recess, but none of the children in his class—including Bart—votes, giving Martin the victory with just two votes. Devastated by Mr. Bergstrom's departure, Lisa takes her grief out on the insensitive Homer, calling him a "baboon". Homer is initially confused and offended until Marge explains that Lisa was lashing out, and so Homer makes up with Lisa by claiming he has never lost anyone special, and then cheers her up by mimicking a monkey. Lisa apologizes for calling him a "baboon". Finding Bart seething over the election result, Homer comforts him by pointing out that being class president would have involved extra work with little reward. Production "Lisa's Substitute" was written by Jon Vitti and directed by Rich Moore. According to Vitti, The Simpsons producer James L. Brooks contributed more to this episode than he did to any other in the show's history. Vitti said the episode was "very controversial" when it was being made because it "came at a point when the staff were just beginning to realize the comedy potential of the show, but we were trapped with these love stories, and just as the staff were starting to get frustrated with the love stories, along came 'Lisa's Substitute': the biggest, huggiest, warmest and fuzziest of them all." Mr. Bergstrom was modeled on the physical appearance of Mike Reiss, a longtime writer and producer on the show. American actor Dustin Hoffman provided the voice of Mr. Bergstrom. Hoffman was not sure if he wanted to be identified with a cartoon show at the time, like many early guest stars on The Simpsons, and therefore used the pseudonym Sam Etic in the closing credits. Sam Etic is a play on the word semitic, alluding to the fact that both Hoffman and Mr. Bergstrom