One of literature's best opening lines is Bradbury's: "It was a pleasure to burn." Those words capture the interest of the reader by pure shock value. As the opening paragraph continues, Bradbury paints a picture of the firehose as a snake and Montag's hands as "some amazing conductor." The metaphors continue with "swarms of fireflies" and "pigeon-winged books."
Bradbury's use of ironic imagery creates a sense of realism to a skeptical reader. Most people view fire with a healthy respect for its power or as a symbol of comfort and warmth. Bradbury eliminates both, making fire something controlled by an authority and used to destroy. (Bradbury references this in the third part of the book when Montag observes the fire of the book-men was not burning, but was warming.)
By turning the common view of fire upside-down, Bradbury begins to show readers how censorship turns the common view of books upside-down. To Bradbury, books are important keepers of information, of philosophy, and of culture. Condemning books based on transitory emotions is no more logical than believing fire can be controlled.