How do they not know?

How could these people in this novel be so unaware of the reality of their society? This question has yet to be answered in Fahrenheit 451. I have a feeling it has to do with the burning of the books. I'm thinking that they are trying to erase the peoples mind and past by burning all of these books. "The books are to remind us what asses and fools we are." This quote made me think that the people living in this world think that they used to be fools, that the books are written about what they were like and what they did in the past. It's almost like they are all brainwashed. How is Clarisse not though? She is the only one who actually knows about the past. Maybe someone found her reading books and that's why she disappeared. Did she die because of it? Why would they be so strict about reading the books? Is it really that bad to know about their past? What was wrong with what was going on in the past? There are so many questions that are yet to be answered. I find it impossible for them to just forget. I'm not sure how the government does it, maybe brainwashing...but how? It could be because they all just got used to living like that, but thinking about it that way just makes it seem a lot more strange to me. Could they be hypnotized? There are so many things to wonder about, how could they just not know? There are many possibilities. Soon, I have a feeling that something is going to come up and answer these questions, and I can't wait to find out.