With a soft swift padding of naked feet, Sim's father ran across the cave. Sim's mother screamed. Sim felt himself torn loose from her grasp. He fell upon the stones, rolling, shrieking with his new, moist lungs! With a soft padding of naked feet Sim's father ran across the cave. The webbed face of his father jerked over him, the knife was poised. It was like one of those prenatal nightmares he'd had while still in his mother's flesh. In the next few blazing, impossible instants questions flicked through his brain. The knife was high, suspended, ready to destroy him. But the whole question of life in this cave, the dying people, the withering and the insanity, surged through Sim's new, small head. How was it that he understood? A newborn child? Can a newborn child think, see, understand, interpret? No. It was wrong! It was impossible. Yet it was happening! To him. He had been alive an hour now. And in the next instant perhaps dead! His mother flung herself upon the back of his father, and beat down the weapon. Sim caught the terrific backwash of emotion from both their conflicting minds. "Let me kill him!" shouted the father, breathing harshly, sobbingly. "What has he to live for?" "No, no!" insisted the mother, and her body, frail and old as it was, stretched across the huge body of the father, tearing at his weapon. "He must live! There may be a future for him! He may live longer than us, and be young!" The father fell back against a stone crib. Lying there, staring, eyes glittering, Sim saw another figure inside that stone crib. A girl-child, quietly feeding itself, moving its delicate hands to procure food. His sister. The mother wrenched the dagger from her husband's grasp, stood up, weeping and pushing back her cloud of stiffening gray hair. Her mouth trembled and jerked. "I'll kill you!" she said, glaring down at her husband. "Leave my children alone." The old man spat tiredly, bitterly, and looked vacantly into the stone crib, at the little girl. "One-eighth of her life's over, already," he gasped. "And she doesn't know it. What's the use?" As Sim watched, his own mother seemed to shift and take a tortured, smoke-like form. The thin bony face broke out into a maze of wrinkles. She was shaken with pain and had to sit by him, shuddering and cuddling the knife to her shriveled breasts. She, like the old people in the tunnel, was aging, dying.