The door leads into a giant dome full of plants, the air moist and very warm, smelling of life and flowers. The same soft light shines down on us from embedded bulbs far above. I know we're underground, but I don't feel the oppression of the earth above me at all.

Socrates runs here and there, examining different rows of growing things, his excitement contagious. I finger the soft leaves of a plant, find myself smiling at the sensation.

Everyone breathes deeply, taking ...