His connection with the frenzied sharks ripping and chewing aimlessly at the fish in spite of the consequences finally snaps something in the old man.  After discussing his physical ailments with the boy, he adds, “In the night I spat something strange and felt something in my chest was broken” (125). This is as clear as the man’s realization appears to the reader.  One can only assume from the last scene where the man is dreaming about the lions, that as the boy had suggested, he will get that well too” (125).
Although Santiago may eventually forget his bond with the fish and his proclamation—“Man is not much beside the great birds and beasts” (68)—Hemingway ensures that the reader will not miss the point.