By section three, "Burning Bright," a clear and visible dichotomy has come to light. Whereas...
Bradbury uses dichotomy in the third and last section of his futuristic novel Fahrenheit 451.
Dichotomy is defined as...
...division into two mutually exclusive, opposed, or contradictory groups; a difference between two opposite things
By section three, "Burning Bright," a clear and visible dichotomy has come to light. Whereas the opposition to the government's absolute control—those fighting to preserve books, knowledge and independent thought—had previously been under tight rein, in this final section Montag's break from societal norms coincides with that of the growing size of an organized resistance: an entire underground movement lives down the river; Faber has technology to support Montag's endeavor to resist; and, by the last page, the government (in response) has bombed the city.
The concussion knocked the air across and down the river, turned the men over like dominos in a line...blew the dust and made the trees above them mourn with a great wind passing away south... And in that instant [Montag] saw the city, instead of the bombs, in the air...and then the city rolled over and fell down dead.
A dichotomy has also developed between Montag and Beatty. Whereas Montag is first presented as a character who does not question the government's laws and absolute control, but instead carries out the burning of books with some satisfaction, he ultimately becomes symbolic of a growing dissatisfaction among society—for if Montag had been the only one, we can infer that there would be no need to bomb the city. Montag—with encouragement from his brief encounters with Clarisse McClellan—has become an agent for change in his society, and is no longer the unthinking and oblivious man he used to be.
The other character most diametrically opposed to Montag is Beatty. He is the head of the firemen and Montag's boss. He is grating and condescending. He is a suspicious man with, ironically, a vast knowledge of forbidden writings. He is a company man: in other words, he supports every action that his government takes. Perhaps what makes Beatty's character so pitiful is that he has much knowledge—has read works by the world's greatest authors—and still turns his back on all that books have to offer. By the last section of the book, Mildred has turned Montag in for owning books. To Montag's surprise, the fire truck pulls up to the Montag household and Beatty confronts Guy. Beatty is symbolic of the government's control of knowledge and, therefore, the people's inability to think independently.
When Beatty threatens Montag and his freedom (they will burn his house and arrest him), Montag turns his flamethrower toward Beatty. Rather than back down, Beatty insults and torments Guy. The other man starts to recite famous literature and hurl needles at Montag. Within a second, Montag pulls the switch on the torch and kills Beatty. His position of open rebellion represents a dichotomy not only between himself and Beatty, but also between a growing number of citizens that refuse to submit to the government's control.
The extremes Bradbury presents allow the reader to understand how far apart the two positions are: the government and the citizens, as well as Montag and Beatty.
The change in Montag is clearly presented in the text. The first line of the story is:
It was a pleasure to burn.
By the story's end, as he sits with others like himself around a campfire in the woods, Montag reflects:
He had never thought in his life that [fire] could give as well as take.