"Science fiction has gotten more accurate as we've gotten closer to the present, because science fiction stories have not only attracted, but also generated current scientists."
- Larry Niven

And again:

'This city, as you know, is built deep beneath the surface of the earth, with only the vomitories protruding... it occurred to me that our cities had been built in the days when men still breathed the outer air, and that there had been ventilation shafts for the workmen. I could think of nothing but these ventilation shafts. Had they been destroyed by all the food-tubes and medicine-tubes and music-tubes that the Machine has evolved lately?

...As I climbed, the rough edges cut through my gloves so that my hands bled. The light helped me for a little, and then came darkness and, worse still, silence which pierced my ears like a sword. The Machine hums! Did you know that? Its hum penetrates our blood, and may even guide our thoughts. Who knows! I was getting beyond its power.

Finally:

"Cannot you see, cannot all you lecturers see, that it is we that are dying, and that down here the only thing that really lives is the Machine? We created the Machine, to do our will, but we cannot make it do our will now. It has robbed us of the sense of space and of the sense of touch, it has blurred every human relation and narrowed down love to a carnal act, it has paralysed our bodies and our wills, and now it compels us to worship it. The Machine develops - but not on our lies. The Machine proceeds - but not to our goal. We only exist as the blood corpuscles that course through its arteries, and if it could work without us, it would let us die."