Why does Coelho use the stars for guiding Santiago, his main character in The Alchemist, through the desert?
Everything that is mentioned in Coelho's The Alchemist has a connection to the universe, to religion, or to some symbolic meaning in one way or another. Every symbol is an omen from which Santiago can learn about the language or soul of the universe. Once Santiago understands as much as he can from the universe, he should achieve his Personal Legend. Therefore, the stars are equivalent to another piece to the puzzle of Santiago's understanding of the universe. Stars represent God's way of showing direction during the night. Stars have guide caravans through the desert like they guide sailors across the sea. If Santiago had not paid attention to the stars, he would have missed out on a very important piece of the geographical map as well as his personal map that is guided by the universe (as he minds the omens, of course). The camel drivers knew to follow the stars during their journey to the Oasis and Santiago learned from their example.
Santiago learned, ". . .no matter how many detours and adjustments it made, the caravan moved toward the same compass point. Once obstacles were overcome, it returned to its course, sighting on a star that indicated the location of the oasis. When the people saw that star shining in the morning sky, they knew they were on the right course toward water. . ."(75). Thus, the stars were valuable guides on the caravan's journey, just like they could be for Santiago on his own journey. That is one of the greatest gifts that Santiago used and developed over the course of the book: he learned to apply all of the omens and lessons of life to his own life's journey. This is one of Coelho's authorial techniques that he uses masterfully throughout the story over and over again with many different symbols and religious omens. For example, Santiago not only learns to read the stars for guidance, but he reads birds, the sand, and the flow of water and wind to help him understand his Personal Legend.