In Brave New World, Huxley depicts a society in which people are totally manipulated. To create such a controlled world, media play a key role in the story. One of the means used to control people in the dystopia (meaning here an undesirable fictional society) is hypnopedia.
Hypnopedia is the name given to a method that consists in hammering in a message into people’s mind. The message is broadcasted during their sleep in a continuous loop as early as when people are children. This procedure is a brainwash and turns out to be really efficient: the characters of the story know by heart all the mottos that were repeated to them. Here is the kind of message children can hear, innocent and unaware, while sleeping: “Alpha children wear grey. They work much harder than we do, because they're so frightfully clever. I'm really awfully glad I'm a Beta, because I don't work so hard. And then we are much better than the Gammas and Deltas” (cf. also the link under this article).
Those names, “Alphas”, “Betas” etc, refer to the different hierarchical categories of people portrayed in the book. The “rank” of these classes follows the Greek letters alphabetically with Alphas being the elite whereas Epsilons form the underclass. This quote, besides being a propaganda message, clearly teaches children to consider the other casts as inferior and wants to highlight the idea of social-classes, so that people always know where they “belong”. Change seems impossible, as it has not even crossed people’s minds.
Hypnopedia is a quick way to instill a message into people’s unconscious minds, which is, to a certain extent, comparable to advertisement’s jingles. We all know by heart a few tunes: which one of us has never sung a stupid slogan when hearing the name of a brand? Isn’t it the same as in Brave New World, when a few characters are on a lift and stupidly repeat in concert a propaganda phrase heard during their sleep?
Alpha children wear grey. They work much harder than we do, because they're so frightfully clever. I'm really awfully glad I'm a Beta, because I don't work so hard. And then we are much better than the Gammas and Deltas.