The importance of direct experience has been so diminished that most people have no desire to even leave their rooms, despite the ease of travel. Indeed, underground society is apparently so uniform that everywhere in the world looks the same. The detail about “unrest concentrated in the soul” suggests that although technological advances and social changes may have transformed human behavior, the human soul remains fundamentally the same. People are still restless and long for novelty and adventure, but they fulfill these desires virtually rather than through direct experience. The details about how the air-ships continue to travel the same paths, even though they have become mostly obsolete, suggests that the Machine operates automatically, requiring little human intervention. This is a potentially dangerous situation, as it means that these systems are taken for granted without any real understanding of how they operate. The air-ships also represent humanity’s apparent conquest of nature, in that people are no longer limited by natural constraints like the inability to fly. But this seems to be a hollow conquest, because humanity is cut off from the natural world’s beauty.