Harry Potter: The Idea of Class
You don't have to have parents who both have magic, either. Hermione Granger, one of Harry's best friends, was born to Muggle parents. Harry's own mother, Lily, came from a Muggle family.
With this definition of the have and the have-not comes prejudice. Even the most kind-meaning people, like Molly Weasley, feel sorry for Muggles because they have to use things like the telephone to talk to other people.
Then there are people like Lucius and Draco Malfoy, who think that only pure-blooded wizards and witches should be allowed at Hogwarts, in the Ministry of Magic, and basically in charge of any area in the wizarding world. This is prejudice of the highest kind, discrimination against people simply because of who their parents were. (Indeed, Draco calls Hermione a "Mudblood"--someone whose parents aren't magical. It doesn't matter to him that she has tremendous magical ability and that she is the smartest student in the class.) This sort of blind prejudice is dangerous, especially when practiced by people who have a lot of power--like Draco's father, Lucius.
Magical ability is not the only way in which people like Draco Malfoy discriminate, however. Draco's family happens to have a lot of money. Ron Weasley's family doesn't. Draco looks down on Ron because of this and calls him all kinds of names. To people like Draco, if you're not rich, you're not worth wasting time on.
Harry has a lot of money, of course, and he doesn't care how much Ron's family has. He sees Ron for what he is--a good friend. Many times, Harry tries to give Ron and his family money; but the proud Weasleys never take it. Harry also wishes that he didn't have all that money so he could know what Ron is feeling.
This same feeling--of seeing people how they really are and not judging them by standards of society--can been seen in Harry's actions toward Hermione. He knows that her parents are Muggles, and he doesn't really care. He has met them, and he thinks they are very nice, if a little overwhelmed by all the magic business. (Harry doesn't really like the Dursleys, of course, but that's because they're never nice to him!)
Harry Potter does his best to ignore class distinctions in his world, but they still exist.
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