“From the bottom of our hearts we ought to thank the modest men who held in their hands the magical Emerald Formula that makes a man master of the world, a formula which they took as much trouble to hide as they had taken to discover it. For however dazzling and bright the obverse of the alchemical medallion, its reverse is dark as night. The way of good is the same as the way of evil, and when a man has crossed the threshold of knowledge, he has more intelligence but no more capacity for love.”
History of Alchemy: Mystics and Seers of All Ages by Reginald Merton (1935)