Harry Potter not only grows in confidence, but with that confidence, he also learns to value his voice and ideas. At the start of the novel, Harry generally expresses himself in short phrases; he realizes that his ideas are unwanted by his Aunt Petunia, Uncle Vernon, and cousin, Dudley. This is seen at the start of chapter two when Aunt Petunia knocks repeatedly on Harry's closet door. She demands,"Get up! Now! . . . Are you up yet" to which, after several repetitions of her demand, he responds, "Nearly" (ch. 2). He does not elaborate, primarily because no one wants to hear his thoughts. This is continually revealed in the early chapters of the novel. For example, when asked to "look after the bacon" for Dudley's birthday breakfast, Harry simply groans (ch. 2). His aunt hears his noise, asks what he said, and he replies, "Nothing, nothing." She doesn't urge an answer because she does not truly care what he said. Aunt Petunia, Uncle Vernon, and Dudley have the majority of the dialogue in the early chapters, as they count Dudley's birthday presents, debate how to leave Harry out of fun events, such as their zoo visit (in honor of Dudley's birthday), and work together to keep Harry's sudden influx of mail away from him.
Even when Harry does try to speak, his voice is ignored. While the family debates how to prevent Harry from going to the zoo, he suggests that they leave him behind, arguing, "I won't blow up the house" (ch. 2). But his words are again overlooked: "they weren't listening." Soon later, he tells Uncle Vernon, "I'm not going to do anything . . . honestly . . .." Again, readers are told that his uncle "didn't believe him. No one ever did" (ch. 2). When Harry does try to share his thoughts, his extended family immediately rebukes him for speaking. For example, while driving to the zoo, Harry tells his family, "I had a dream about a motorbike . . . it was flying" (ch. 2). Though he was simply making a factual statement about a dream he had, Uncle Vernon angrily retorts:
MOTORBIKES DON'T FLY!
At the start of the novel, Harry's words are ignored, undervalued, silenced, and even rebuked. Humorously, one of Harry's most elaborate conversations early in the novel is with a snake at the zoo.
I know . . . It [people tapping on your glass] must be really annoying . . .
Where do you come from anyway? . . .
Was it nice there? . . .
Oh, I see - so you've never been to Brazil? . . .
The snake responds in gestures to Harry's questions- that is, until Harry accidentally uses magic to free the snake. Then, the snake seems to speak to Harry in actual language, saying, "Brazil, here I come . . . Thankssss, amigo" (ch. 2). The fact that one of the longest conversations that Harry has in the first few chapters is with a snake shows how little his family cared about his words; because he grew up with people who did not value him, Harry begins the story saying very little.
In chapter three, Harry begins to receive mail, unexpectedly. His family works together to keep this mail away from him; they seem afraid of what the letter might say. Because he was not used to receiving material things and gifts, including mail, he grows frustrated with their interceptions. He shouts out,
I WANT MY LETTER!
Uncle Vernon responds, "OUT!" (ch. 3)
Though Harry makes a bold attempt at speech in this scene, he is again silenced. When other changes begin to happen, such as Harry being offered "Dudley's second bedroom," Harry questions the decision. His uncle responds, "Don't ask questions!" again silencing his voice. Continually, Harry's voice is minimized and silenced at the start of the book. Because of this, he learns to remain quiet.
In chapter 6, as Harry boards the train for Hogwarts, we see how quiet he is with fellow students at first. He's learned to keep himself quiet from his interactions with his family. When Ron asks if anyone is sitting in his compartment, because the rest of the train is full, he replies by "sh[aking] his head," rather than talking. As the twins come in and introduce themselves, Harry doesn't say anything except, "bye." And, when Ron asks if he is really "Harry Potter," he responds by nodding, rather than words. It takes several paragraphs for Harry to begin talking with Ron and other students.
Even at Hogwarts, some characters try to quiet and minimize Harry's voice and ideas. For instance, when he goes to Potions class, he meets Professor Severus Snape, who questions his magical knowledge and attempts to point out his lack of learning: "What would I get if I added powdered root of asphodel to an infusion of wormwood?," he asks Harry. Harry replies, "I don't know, sir" (ch. 8). Even after he leaves the Dursley's home, Harry's voice is till ignored or belittled by some characters at Hogwarts. Overall, though, friends such as Ron, Hagrid, and Hermione start conversations with Harry that reveal to him how much his voice matters.
Through his friendships and his relationships with professors at Hogwarts, Harry learns to value his ideas and his voice. This is seen at the end of the novel when Harry decides to risk his well-being (and his ability to stay at Hogwarts) to make sure that Voldemort did not get access to the sorceror's stone. Even when he faces the threat of expulsion, Harry tells Hermione and Ron, "I'm going out of here tonight and I'm going to try to get the Stone first" (ch. 16). When his friends challenge him, he shouts,
SO WHAT? . . . Don't you understand? If Snape gets hold of that stone, Voldemort's coming back! . . .
By the end of the first book, Harry has learned the value of independent thinking. He learns to voice his ideas, not allowing others to make him doubt himself.