Jack Vance

“ Reak, the younger of the women, gnawing on the bit of carrion, made no reply.
Finn said hollowly, "Why do we worry ourselves? Food is ever more difficult, and we are the last of all men."
"No, no," spoke Reak. "Not the last. We saw others on the green mound."
"That was long ago," said Gisa. "Now they are surely dead."
"Perhaps they have found a source of food," suggested Reak.
Finn rose to his feet, looked across the plain. "Who knows? Perhaps there is a more pleasant land beyond the horizon."
"There is nothing anywhere but waste and evil creatures," snapped Gisa. ”

“ Presently the Relict would die of poison or rent bowels or skin lesions, while the Organism relaxed in the dank black grass. Or the Organism might seek to eat the Relict; and the Relict would run off in terror, unable to abide any part of the world—running, bounding, breasting the thick air ”

“ From the two billions of men, only a few survived—the mad. They were now the Organisms, lords of the era, their discords so exactly equivalent to the vagaries of the land as to constitute a peculiar wild wisdom. ”

“ Man had dominated Earth by virtue of a single assumption: that an effect could be traced to a cause, itself the effect of a previous cause.
Manipulation of this basic law yielded rich results; there seemed no need for any other tool or instrumentality. Man congratulated himself on his generalized structure. He could live on desert, on plain or ice, in forest or in city; Nature had not shaped him to a special environment.
He was unaware of his vulnerability. Logic was the special environment; the brain was the special tool. ”

“ Finn argued calmly.
No one could find grounds for disagreement.
"Here is what I propose," said Finn. "Notice this tall peak. Notice the layers of hard air. They bump into the peak, they bounce off, they float in and out and disappear past the edge of sight. Let us all climb this peak, and when a sufficiently large bank of air passes, we will throw ourselves on top, and allow it to carry us to the beautiful regions which may exist just out of sight."
There was argument. The old man Tagart protested his feebleness ”

“ They were fast dying out, for sanity provided no leverage against the environment. Sometimes their own minds sputtered and jangled, and they would go raving and leaping out across the plain.
The Organisms observed with neither surprise nor curiosity; how could surprise exist? The mad Relict might pause by an Organism, and try to duplicate the creature's existence. The Organism ate a mouthful of plant ”