Themes are the fundamental and often universal ideas explored in a literary work.
Knowledge is absolutely crucial to Harry’s survival, and, fittingly, his experiences as a boarding school student provide the most prominent narrative arcs in the series. Unlike contemporary students, who have access to computers and other knowledge-accelerating technology, Harry’s education must happen slowly and carefully over an extended period of time, often via trial and error. For Harry, the acquisition of knowledge is explicitly and often painfully linked to the passage of time. For example, Harry must live with his last remaining blood relatives, the hideous Dursleys, for eleven years until Dumbledore finally decides Harry is ready to experience life as a Wizard. Likewise, Harry must wait until he is no longer an “underage wizard” before he is allowed to safely use his magic outside of Hogwarts. (Harry’s defiance of this rule—in self-defense—provides the main conflict for the first few chapters of Book V). Harry must also wait nearly sixteen years until he is allowed to know the truth about his scar and hear about the prophecy that was made before his birth. He must wait for Dumbledore to finally explain Harry’s kill-or-be-killed link to Voldemort. He does not learn the mission of the Order of the Phoenix until he discovers it himself.
In Book V, Harry’s education is put in jeopardy for the very first time, and the true value of that education becomes fully clear. Hogwarts is gradually overtaken by the corrupt Ministry of Magic, and High Inquisitor Dolores Umbridge refuses to let the students learn proper Defense Against the Dark Arts. Concerned, the students take learning Defense into their own hands, forming a secret study group, the D.A., and spending the semester meeting privately to learn and practice Defense spells. Ultimately, their hard work and practice save them at the end of the novel, where they use their newly developed skills to escape the Death Eaters unharmed. Had the students not been so stubbornly proactive, they might not have survived, and they can appreciate the true importance of what they are learning at Hogwarts in an entirely new way.
At the start of the school year, the Sorting Hat warns students that they need to stand together. Unfortunately, the House system at Hogwarts automatically divides students into four houses, mirroring the ideological split of the school’s four founders. Coupled with a highly competitive Quidditch Cup tournament and separate dormitories, students at Hogwarts are inherently segregated. All of Harry’s close friends—Ron, Hermione, Ginny, and Neville—are members of Harry’s House, Gryffindor. Houses are not the only form of segregation at Hogwarts. Like Slytherin founder Salazar Slytherin, some Hogwarts students believe that only pure blood Wizards should be allowed to study at Hogwarts—Mudbloods and half bloods are often ostracized or mocked. Even outside of the Wizarding community, terrible segregation exists. The giants Hagrid visits in the mountains are not welcoming to others, and the Centaurs constantly chase outsiders out of the Forbidden Forest.
Lord Voldemort preys on this internal splintering, as does the Ministry of Magic. Ultimately, Ministry employee Dolores Umbridge is able to use this petty competition to form an Inquisitorial Squad of students, which consistently thwarts Harry’s attempts to stop Voldemort, making his work far more difficult. Now more than ever, Hogwarts must stand together—not only to defeat Voldemort but to protect themselves against corrupt faculty members that threaten their education.