Perhaps, one can simply quote from DH Lawrence's poem, "The Snake".
"I have something to expiate, a pettiness".
E. Hemingway is too macho (self-styled) to feel like this, of course.
This must be one of the most anthropocentric books ever written for all that the hero feigns empathy with his "catch" and some have even held the marlin to represent Jesus.
Imagine the book got the Pulitzer and the Author the Nobel!