Hypnopaedia is first introducted in Chapter II of this dystopian classic, and is shown to be yet another form of conditioning babies in their early years to instil within them certain moral principles. Whilst babies sleep they are played a message repeatedly over and over again that makes them accept their social role in the heirarchy of this society and encourages them not to challenge their social position. Note what the text says about hypnopedia:
Wordless conditioning is crude and wholesale; cannot bring home the finer distinctions, cannot inculcate the more complex courses of behaviour. For that there must be words, but words without reason. In brief, hypnopaedia.
Hypnopaedia is therefore illustrated as being a form of moral inculcation that occurs in babies whilst they are asleep. It is based on the form of subliminal messages that shape the thinking and attitudes of babies, making them happy with their lot in life and unquestioning about why they are the way they are.