LitCharts assigns a color and icon to each theme in Simon vs. the Homo Sapiens Agenda, which you can use to track the themes throughout the work.
Agency and Control
Identity and Assumptions
Relationships and Empathy
Family, Change, and Growing Up
Summary
Analysis
While washing his makeup off that afternoon, it suddenly hits Simon that Blue could be Martin—he shares a name with former president Martin Van Buren. Simon thinks through what he knows about Martin, but keeps coming back to his belief that Martin is clearly not gay. Abby appears, interrupts Simon, and tells him to leave some of the eyeliner on. She says that she and Nick are taking him out, and they're going to spend the night at her house. As Abby insists they need to go into Atlanta, Simon continues to mull over the Martin problem. He wonders if Blue was just a joke, but decides he can't think about it.
When Simon finds himself considering the possibility that Martin is Blue, it shows that Simon is now fully aware of how little he knows about his classmates. His firm belief that Martin is straight complicates some of this, but the fact that Simon is even considering this shows that he's even more aware of the assumptions he's made about people and understands that they've likely compromised his interpretation of his world.
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Abby and Simon meet Nick in the parking lot. Abby asks if they've talked to Leah, and Nick carefully suggests they not invite Leah. Simon knows she'd be weird, self-conscious, and snappy, so he agrees. They stop at a couple of shops, including a feminist bookstore with a good LGBT section. Abby buys Simon a book and then they head back to Midtown to a restaurant called Webster's. Simon notices rainbow banners and asks if it's a gay bar. It is, but it also has a restaurant where underage guests can eat.
Gay bars are places where gay people like Simon are the default and their sexuality is normalized—in this situation, Abby and Nick are the ones on the outside. This experience will then remind Simon that there are places in the world that are more accepting of his identity than his small southern town and high school.
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There's a short wait, during which Simon, Abby, and Nick giggle over the menu items, all of which are innuendos. Simon tries to not make eye contact with the other guys there and finally excuses himself to the bathroom. On his way back, a college guy taps Simon on the shoulder and calls him Alex. Realizing his mistake, he introduces himself as Peter and buys Simon a green apple martini. Peter is complimentary and wants to know if Simon is a student. Peter buys Simon a shot of something orange and sweet, teaches him how to take a shot, and Simon begins telling Peter all about Abby and Nick.
Though Peter is certainly making wild assumptions about Simon (particularly about his age), Simon goes along with it in part because hanging out with Peter is something like wearing a mask: Simon gets to try out being gay with other gay guys who seem far more comfortable being out, which he doesn't see at home in Shady Creek.
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All of Peter's friends are nice and cute guys, and someone passes Simon a beer. He drinks it even though things are already spinning. Simon finds himself telling the group about the Martin fiasco, but Peter leans forward and asks Simon if he's in high school. Simon admits he's only seventeen. Peter steers Simon into the restaurant to Abby and Nick, deposits him in the booth, and hugs him goodbye. Simon digs into his cold hamburger, says he loves it here, and struggles to count how many drinks he had.
Peter stands as an example of a better way to deal with misguided assumptions: after realizing that Simon is underage, Peter makes sure Simon gets safely back to Nick and Abby. Simon's apparent happiness with the situation suggests he enjoyed getting to be his true self in public for the first time.
Nick and Abby walk Simon to the car as Simon talks about how cute Peter was. He says hi to everyone on the street and doesn't protest when Nick puts him into the front seat in case he needs to vomit. Simon suddenly asks where they're going. When Abby says they're going to her house, Simon insists they need to go home so he can get his Elliott Smith tee shirt. He says he never went to any of Smith's shows because Smith committed suicide when they were five. Abby and Nick exchange a look and then Abby turns around.
Abby and Nick's decision to turn around shows them very kindly recognizing a new-to-them part of Simon's identity. This suggests that Simon's friends may be more willing to accommodate changes than Simon was initially willing to give him credit for, especially given how much they're humoring him.
Simon tells Abby he loves her and invites her to be his sister, insisting he needs new ones—Alice and Nora are changing too much. He doesn't think it matters when Abby points out that he's changing too.
Simon's comment about Alice and Nora reveals just how insecure he feels in his changing family right now.
When they get to Simon's house, Simon lurches inside. He finds Mom and Dad watching TV. They ask him why he's home, and Simon's explanation clearly shows that he's drunk. He starts laughing uncontrollably. Dad makes Simon sit down, makes sure Abby didn't drink and drive, and then Mom goes outside to send Abby home. Dad insists that they have to cancel Simon's night out since Simon is drunk, to which Simon points out that at least he's not lying about anything. Dad looks suddenly very angry. Simon asks if he's upset that he can't make fun of gay people anymore and drunkenly giggles. Dad just stares.
When Simon calls Dad out on his affinity for making jokes about gay people, it highlights just how insecure and unsupported Simon feels in his family. Coming out means that all family members are now well aware that Simon is hurt by things he's heard his family members say without thinking. This underscores the importance of understanding that words have the power to hurt people, even if that wasn’t the intention.
Mom comes back inside and sends Simon to get water. Mom and Dad talk for a moment alone and then come into the kitchen. Simon admits that this is the first time he's done this, so Dad says they'll ground him for two weeks. They'll let him perform in Oliver, but they take his phone and laptop.
While Martin taking control of Simon's story was dangerous, Mom and Dad take away Simon's agency as a way to protect him. This suggests that while the novel overwhelmingly insists that it's bad to take away someone's agency, doing so has its place.