At the beginning of the story, the man is determined and invincible, but as time goes by, he realizes that he was wrong and that he is in great danger.
We can arrive at this answer because:
The man is very brave and with the feeling of invincibility, however, over time and with the environment increasingly violent, the man realizes that he is in serious trouble. His body is not supporting the trip and he realizes that he is very fragile.
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