Quote 7
It was cold now in the time before daylight and he pushed against the wood to be warm. I can do it as long as he can, he thought. And in the first light the line extended out and down into the water. The boat moved steadily and when the first edge of the sun rose it was on the old man’s right shoulder. (3.1)
The old man’s own determination is driven by what he sees in the fish.
Quote 8
"It’s steady," the old man told him. "It’s too steady. You shouldn’t be that tired after a windless night. What are birds coming to?" (3.14)
The old man implicitly compares himself to the birds, believing that feeling tired is something to be ashamed of.
Quote 9
"I don’t think I can eat an entire one," he said and drew his knife across one of the strips. He could feel the steady hard pull of the line and his left hand was cramped. It drew up tight on the heavy cord and he looked at it in disgust.
"What kind of a hand is that," he said. "Cramp then if you want. Make yourself into a claw. It will do you no good." (3.31, 3.32)
The old man is mentally determined, but disappointed in the lack of endurance he sees in his body.