"Leibniz discovered his future with the help of a Nuremberg society of alchemists. ...In private ...he exhibited an avid interest in the subject throughout his life—as did many of his contemporaries, such as Isaac Newton. Indeed, he was so certain that he would one day soon discover the means to turn lead into gold that at one point he fretted that the resulting oversupply of the yellow metal might drive down the price and thus deprive him of hard-earned profits."