Caroline continued. "So they learn where the pleasure points are by hook or
  crook, then stimulate themselves directly. And when they get it right, they
  never do anything else. They get everything maximized, tuned up, and they just
  sit there forever enjoying it."

  "Right. Now is a creature that is doing that, not interacting with the world
  at all any more, human?"

  Caroline thought about it. "No."

  "Prime Intellect thinks otherwise. But it has its doubts."