In 1964, literary critic and author Alfred Kazin explained that Hemingway, journalist and minimalist, sought the perfect sentence to the point of almost obsessive behavior. Kazin stated that Hemingway sought that "true sentence" that
would have the primacy of experience, that would relive a single unit of experience.
Kazin has captured the two requisites of Hemingway's sentences. Because he had been a journalist, Hemingway sought objectivity and succinctness. Yet, his near and frequent experiences with death impelled him to seek to write not just a succinct and minimal sentence with no transitions, no superfluous clauses or phrases, but also to have a sentence that would, through its "cadence" and subtle "culminating word," unsettle the readers just enough to make them take notice of a different way of saying something. Hemingway sought to communicate an almost metaphysical experience in a simple, but intimate sentence.
The succinct and minimal, but often intimate sentences of Hemingway are of simple diction, usually monosyllabic words of Anglo-Saxon, as opposed to Latin, origin. Structurally, Hemingway writes simple sentences, rather than complex ones. With little or no figurative language, they are more jounalistic rather than literary in the effort for direct meaning to be apparent.
When hemingway says he is on a quest for a perfect sentence he means the right words that will fit in with the whole novel. His use of diction and syntax is hope. When the old man goes eighty four fishless days, and when he is battling the marlin, and when he is fighting off the sharks all he can have is hope. I think the sentence that could qualify as a perfect sentence is the first sentence of the novel which is "He was an old man who fished alone in a skiff in the Gulf stream and he had gone eighty-four days now without taking a fish." I think this qualifys as a perfect sentence because after going eighty-four fishless days he has hope that the eighty-fifth day would be lucky. When he hooks the marlin all he has is hope that he will have the strength to catch him.
*by the way an english teacher helped me with this