The books symbolize imagination. When Montag and the others burn the books, they are doing so to protect society from the evils of imagination. Television symbolizes social conformity, because people watch television instead of interacting and reading and using their imagination.
I could never make myself care very much about the writings of Ray Bradbury. He seems like a writer with a good imagination but not a strong intellect. I cannot take him very seriously, even when he chooses a serious topic, as he often does. He was highly successful and made a lot of money. I think his commercialism interfered with his creativity. In Fahrenheit 451 he writes about a society in which the government is trying to stamp out reading and independent thinking. This would be serious if it could be taken seriously, but it is hard to believe that Bradbury himself ever foresaw this as a real possibility and a real threat. This sort of thing was done in the Dark Ages. It was something that happened in the past, not something that is going to happen in the future. Even Hitler didn't try to burn all the books. Fahrenheit 451 is more for amusement than for serious consideration. The really good dystopian novels are Brave New World and 1984. I don't consider Bradbury's "symbols" important because I don't consider the novel anything more than a "knockoff" of really good books like those of Huxley and Orwell.
To identify symbols in a work, look for something concrete, something visual, that makes an important point in the book. Symbols are not always obvious, and sometimes require a good bit of thought.
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