In Paulo Coelho's novel, The Alchemist, the Englishman is searching for the alchemist in order to learn the secret of turning common metals into gold. Part of his philosophy of life deals with the soul.
'That's the principle that governs all things,' he said. 'In alchemy, it's called the Soul of the World. When you want something with all your heart, that's when you are closest to the Soul of the World. It's always a positive force.'...He said that it was not just a human gift, that everything on the face of the earth had a soul...
In essence, the Englishman's philosophy first is that all things have souls: people, plants, animals...even "a simple thought." In light of this basic principle, it seems that he believes that the soul draws closer to the Soul of the World by wanting something "with all his heart"—that this is a positive force that moves one along in life's journey.
In Santiago's case, the Englishman believes that his time spent at the crystal shop has brought the young boy closer to the Soul of the World because his time with the crystal merchant led the boy to continue his pursuit of his Personal Legend—which he wants with all his heart—and in this way, it brought Santiago closer to the Soul of the World.