The Old Man and the Sea
How we cite our quotes:
This will kill him, the old man thought. He can’t do this forever. But four hours later the fish was still swimming steadily out to sea, towing the skiff, and the old man was still braced solidly with the line across his back. (2.80)
The fish possesses a determination equal in magnitude to Santiago’s.
He had pushed his straw hat hard down on his head before he hooked the fish and it was cutting his forehead. He was thirsty too and he got down on his knees and, being careful not to jerk on the line, moved as far into the bow as he could get and reached the water bottle with one hand. He opened it and drank a little. Then he rested against the bow. He rested sitting on the un-stepped mast and sail and tried not to think but only to endure. (2.82)
The old man is best able to endure when he can distract himself from thinking about his plight or pain.
"Fish," he said softly, aloud, "I’ll stay with you until I am dead." He’ll stay with me too, I suppose, the old man thought and he waited for it to be light. (2.105, 2.106)
The old man recognizes that the fish possesses an endurance to match his own.