As the caravan crosses the Sahara, Santiago and the Englishman each make an effort to gain new insights by practicing the other's method of learning: Santiago reads the Englishman's books about alchemy, and the Englishman spends several days observing the caravan and the desert. When the Englishman asks Santiago what the boy learned about alchemy from reading his books, Santiago sums up his reading in a few short sentences (page 83 Gold Cover; pages 85-86 Red Cover). What does he say he learned?