In The Old Man and the Sea, the author's thematic concern revolves around the themes of struggle, perseverance and the ability to rise above defeat, even in the face of overwhelming odds. The old man, Santiago, fights the marlin for three days, and although he loses the fish to sharks, his determination, strength and resilience in the face of failure demonstrate his capacity to rise above defeat. This theme of persistence and the human spirit's ability to endure is central to the novel.