Captain Beatty gives Montag a lecture because he does not come to work when he begins to question his work as a fireman and steals a book.
Montag is a fireman, but he is not the kind of fireman that puts out fires. He starts fires, to burn books. In Montag’s world, all houses are fireproof to ensure that books can burn and the city won’t.
At first, Montag does not have a problem with his life. He has never thought to question anything until he has a conversation with a teenager named Clarisse who asks him if he is happy. This is not a question he thought to ask himself. He realizes that he is not. He goes to work and asks Beatty about the history of fireman, and Beatty tells him the first fireman was Benjamin Franklin. They are interrupted by a call. Someone has a book.
When he sees a woman decide to go to her death with her books, rather than giver herself up, he begins to question everything. He steals a book, even though he is taking an enormous risk, because he is curious about what would make the woman do such a thing.
Beatty tells Montag that he is “full of bits and pieces” because he is a fire captain, but it is more than that. Somehow, he is extremely well read. When Montag does not show up for work, Beatty comes to him. He knows exactly what is going on. He tells Montag he has seen it all.
"Every fireman, sooner or later, hits this. They only need understanding, to know how the wheels run. Need to know the history of our profession. They don't feed it to rookies like they used to. …Only fire chiefs remember it now." Puff. "I'll let you in on it." (Part I)
Beatty’s purpose in the lecture he gives Montag when he comes to his house when Montag calls in sick is to explain to him why their society is better, and why it is pointless to become curious about books. He knows that what Montag is experiencing is basically a crisis of faith. He does not know if he can conform to society any more.
While Beatty describes how society was “improved,” it does not really seem like much of an improvement.
"School is shortened, discipline relaxed, philosophies, histories, languages dropped, English and spelling gradually neglected, finally almost completely ignored. Life is immediate, the job counts, pleasure lies all about after work. Why learn anything save pressing buttons, pulling switches, fitting nuts and bolts?" (Part I)
Beatty is a paradox. He is not really evangelizing the benefits of his advanced society. It almost seems sarcastic. What he describes is not a world most of us would want to live in. Also, why would a man who talks about how terrible books are be able to quote from Shakespeare and know history so well? Beatty is clearly well read.
Is Beatty really trying to convince Montag to give up books, or is he actually trying to make him a rebel? Answering this question is up to the reader to a certain degree. It is an interesting point to ponder. When Montag is caught, he has to kill Beatty in order to get away. However, Beatty is just doing his job. If he gave himself up as a book reader, he would be as good as dead anyway. They have the mechanical hound for that.
Montag decides that he is not going to conform. He is going to try to be happy. He will live in a world of books, even if that means one book at a time. A world without books, and individuality, is not a world where you are really alive. This is Bradbury's message to us. Happiness comes from really experiencing human relationships, not watching television and driving fast. Books are not the enemy because they are slow. They capture the human spirit, because they contain ideas.