In addition to fate, how might "man versus nature" also be one of the themes of "The Alchemist"?
In Part I, Santiago struggles with the needs of his flock. He knows that his love for his sheep, and they for him, is somewhat unnatural, in the sense that both men and beasts have given up their true identities in exchange for protection and security. "If I became a monster today," Santiago muses, "and decided to kill them, one by one, they would become aware only after most of the flock had been slaughtered." It is not an ideal state for man or beast.
In Part II, the man vs. nature struggle takes a different turn. Here, Santiago must learn to deal with the demands of the desert on its terms rather than his own. The camel driver tells him: "Once you get into the desert, there's no going back, you have to worry about the best way forward." From the desert, then, Santiago understands that the only thing worth worrying about is the present.
During his epic battle to bring the wind, sun, and sand to his aid, the boy learns how to respect nature rather than dominate it. He also teaches nature to respect man. When the haughty wind says, "You can't be the wind. We're two very differnt things," the boy replies, "That's not true. I have inside me the winds, the deserts, the oceans, the stars, and everything created in the universe."