"And you live forever." He gripped her shoulders and looked into her wide eyes. He had to expel the demons of terror from her. A woman five months pregnant couldn't go on this way. He was suddenly shocked by how thin she had grown, and she never stopped shivering under his hands.
"You won't grow old," he said slowly. "We'll be together forever, Eileen. And our children won't die either."
She looked away from him, and sudden bitterness twisted her mouth. "I wonder," she said thinly, "whether immortality is worth having—on this planet."
Suddenly she stiffened, and her lips opened to scream again. Langdon forgot the hurt of her words and looked wildly about the room. But there was only the furniture and the firelight and the weaving shadows. Inside the blood-red windows, the room was sane and real and human.
Eileen shrank against him. "It's over there," she gasped. "Over there in that corner, creeping closer—"
Langdon's face grew bleak, and there was a desolation rising in him. Illusions of one sort or another were part of daily life on Tanith, but they had reality in that they were produced by physical processes and more than one person could perceive them. But hallucinations were another story.
He thought back over two hundred years to the first attempts to colonize. Of an initial three hundred or so, over two-thirds had left within the first three years. And many of them had been insane when the ships took them home.
Men came to Tanith and stayed if they could endure it. But if they couldn't, and tried to stay anyway, they soon fled from the unendurable madness of its reality to a safer and more orderly madness of their own.
From what he had heard, few of them were cured again, even back on Terra.