I’ve spent more time in underground while living in New York City than I’ve ever been in my entire life. In fact the only time I’d ever been underground before this (aside from previous visits) was once when I was eleven I took a tour of a cave. When I was in the cave at one point the tour guide shut off the lights and it was the darkest experience I’ve ever had, the complete absence of light. Then she said that if person lived in a cave all their life and had babies in that cave and their children had babies in the cave the third generation would, through evolution, be born without eyes.

Living in New York City’s ‘pale’ underground could turn a man into a moth.
“Then he returns to the pale subways of cement he calls his home.”
The Man-Moth makes his home in the subway riding back and forth night after night and occasionally he emerges to the surface and ‘scales’ the outdoor tunnels of cement which don’t provide enough protection from the earth’s atmosphere for him.
“He thinks the moon is a small hole at the top of the sky, proving the sky quite useless for protection.”
In Manhattan you are inside even when you’re outside, without the lid. The concrete ground rises up around you high into the atmosphere. As you scale through the outdoor tunnels you look up to the sky beyond the buildings to see traces of the sun and the moon with almost no chance of stars. It doesn’t provide enough protection for a moth, but for a man it sounds almost like a cage. Living in the ‘World Capital’ as Jonathan Lethem puts it appears to me like putting ourselves into a cage similar to the cages we put the other animals on earth we consider ourselves superior to. If we make the deepest darkest part of that cage our home we may adapt like the Man-Moth, left only with our tears, our last piece of humanity; there is always water if you dig deep enough underground.
“Then from the lids one tear, his only possession--if you watch, he’ll hand it over, cool as from underground springs and pure enough to drink.”