From the beginning there had been a revolutionary group. Its name had changed several times, and Matt had no idea what it was now. He had never known a revolutionary. He had no particular desire to be one. They accomplished nothing, except to fill the Hospital's organ banks. How could they, when the crew controlled every weapon and every watt of power on Mount Lookitthat? If this was a nest of rebels, then they had worked out a good cover. Many of the merrymakers had no hearing aids, and these seemed to be the ones who didn't know anyone here. Like Matt himself. In the midst of a reasonably genuine open-house brawl, certain people listened to voices only they could hear.

Ch. 2 : The Sons Of Earth - A Gift From Earth (1968)