Secrecy as deep as this is past possibility without nonexistence as well. — Isaac Asimov

The house was somehow very lonely at night and Dr. Darell found that the fate of the Galaxy made remarkably little difference while his daughter's mad little life was in danger.

Remarkable what a fragile flower romance is. A gun with a nervous operator behind it can spoil the whole thing.

Every human being lived behind an impenetrable wall of choking mist within which no other but he existed. Occasionally there were the dim signals from deep within the cavern in which another man was located — so that each might grope toward the other. Yet because they did not know one another, and could not understand one another, and dared not trust one another, and felt from infancy the terrors and insecurity of that ultimate isolation — there was the hunted fear of man for man, the savage rapacity of man toward man.