How did Guy Montag change throughout the novel Fahrenheit 451?
Initially, Montag believes in and supports the culture of which he is a part. He enjoys his role as a book-burning fireman. As the opening line of the novel tells us, Montag finds:
It was a special pleasure to see things eaten, to see things blackened and changed. With the brass nozzle in his fists, with this great python spitting its venomous kerosene upon the world, the blood pounded in his head, and his hands were the hands of some amazing conductor playing all the symphonies of blazing and burning to bring down the tatters and charcoal ruins of history.
But his ideas soon begin to change. He meets Clarisse, who "think[s] too many things," and he too starts to ponder:
What incredible power of identification the girl had; she was like the eager watcher of a marionette show, anticipating each flicker of an eyelid, each gesture of his hand, each flick of a finger, the moment before it began. How long had they walked together? Three minutes? Five? Yet how large that time seemed now.
It's not only his encounter with Clarisse that beings to initiate a change in Montag. He has hardly arrived home from meeting her when he finds his wife, Mildred, has attempted suicide. She is barely breathing and near her he finds an empty pill bottle:
The object he had sent tumbling with his foot now glinted under the edge of his own bed. The small crystal bottle of sleeping-tablets which earlier today had been filled with thirty capsules and which now lay uncapped and empty in the light of the tiny flare.
He had believed he was happy. He had thought Mildred was content. Now he begins to understand that something is wrong with both of their lives.
He meets Clarisse again. She tells him he is different:
"When I said something about the moon, you looked at the moon, last night. The others would never do that. The others would walk off and leave me talking. Or threaten me. No one has time any more for anyone else. You're one of the few who put up with me. That's why I think it's so strange you're a fireman, it just doesn't seem right for you, somehow."
He felt his body divide itself into a hotness and a coldness, a softness and a hardness, a trembling and a not trembling, the two halves grinding one upon the other.
As he feels his body "divide" itself, his change is truly beginning to take hold. He becomes interested in the world of books. He grows fascinated with what they offer beyond the opportunity to burn them. He realizes he wants more than his dulled-down, routine life. Montag begins to think for himself and to seek out the people who read. By the end of the novel he has been transformed from a fireman, a symbol of conformity to the system, to a renegade rebel living outside his society with others like him, for the first time truly alive.
After meeting Clarisse, Guy Montag begins to question things in ways he's never done before. Previous to this encounter, Guy simply went about his business as a fireman and did as he was told. In their first meeting, Clarisse tells Montag that she had once heard that firemen used to put fires out, rather than start them. Montag laughs. Clarisse replies:
"You laugh when I haven't been funny and you answer right off. You never stop to think what I've asked you."
This is a key and blatant moment in the early part of the novel where Clarisse clearly challenges Montag to "think" about things. As she leaves Montag, she asks him if he is happy. Ordinarily, Montag would not give such a thing, or anything, a second thought. But Clarisse sparked some curiosity in him and he begins to question if he is happy. As far as Montag realizes at this point, no one has ever challenged him to think in this way:
How rarely did other people's faces take of you and throw back to you your own expression, your own innermost trembling thought?
As the novel continues, Montag's curiosity grows. He continues to question his life, his role as a fireman, and the supposed illegality and evil of books. He stockpiles books he steals from fires and reads. He questions his wife's lifestyle and realizes any significant connection they may have had is lost. Eventually, Montag's curiosity gets him into trouble with Beatty and higher authorities. But by this time, he has passed the point of no return as he becomes determined to question things, gain more knowledge, and find greater significance in his life.