When he decides to go, his father only advised him, "Travel the world until you see that our castle is the greatest and our women the most beautiful". In his journey, Santiago sees the greatness of the world, and meets all kinds of exciting people like kings and alchemists. In the end of the novel, he finds that "treasure lies where your heart belongs", and that the treasure was the journey itself, the discoveries he made, and the wisdom he has caught.
"The Alchemist", is an exciting novel that is covered with optimism. It is the kind of novel that tells us that everything is possible as long as we really want it to happen. The novel mostly tells us the meanings philosophically. May be it will be difficult to understand, but as Coelho states "simple things are the most valuable and only wise people appreciate them".
As the center of message exists in the novel is the alchemist himself words when he appears to Santiago in the form of an old king, "when you really want something to happen, the whole universe will automatically conspire so that your wish comes true".