Huxley takes the title Brave New World from Shakespeare's The Tempest. The title is apt because John the Savage knows Shakespeare by heart and quotes him often. When John says "oh brave new world that has such people in it" to describe the World State, he is being ironic. He is not impressed with the shallow, superficial lives people live. He finds it tragic that the humans in this futuristic society know nothing of sacrifice, suffering, real religion, literature, or the arts. He considers it a great loss that they have traded deep relationships for security. Mond, however, argues that the comforts and well-adjusted lives people have in the World State are a fair trade-off for giving up passion, art, and freedom.
Huxley is being ironic when he titles his book Brave New World. He writes about this dystopia to warn people against allowing this kind of drugged, shallow, and dehumanizing world to develop.