Sir Isaac Newton was a towering genius in the history of science, he knew he was a genius, and he didn’t like wasting his time. Born on Dec. 25, 1642, the great English physicist and mathematician rarely socialized or traveled far from home. He didn’t play sports or a musical instrument, gamble at whist or gambol on a horse. He dismissed poetry as “a kind of ingenious nonsense,” and the one time he attended an opera he fled at the third act. Newton was unmarried, had no known romantic liaisons and may well have died, at the age of 85, with his virginity intact. “I never knew him to take any recreation or pastime,” said his assistant, Humphrey Newton, “thinking all hours lost that were not spent on his studies.”

No, it wasn’t easy being Newton. Not only did he hammer out the universal laws of motion and gravitational attraction, formulating equations that are still used today to plot the trajectories of space rovers bound for Mars; and not only did he discover the spectral properties of light and invent calculus. Sir Isaac had a whole other full-time career, a parallel intellectual passion that he kept largely hidden from view but that rivaled and sometimes surpassed in intensity his devotion to celestial mechanics. Newton was a serious alchemist, who spent night upon dawn for three decades of his life slaving over a stygian furnace in search of the power to transmute one chemical element into another.

Newton’s interest in alchemy has long been known in broad outline, but the scope and details of that moonlighting enterprise are only now becoming clear, as science historians gradually analyze and publish Newton’s extensive writings on alchemy  a million-plus words from the Newtonian archives that had previously been largely ignored.

Speaking last week at the Perimeter Institute for Theoretical Physics in Waterloo, Ontario, William Newman, a professor of the history and philosophy of science at Indiana University in Bloomington, described his studies of Newton’s alchemical oeuvre, and offered insight into the central mystery that often baffles contemporary Newton fans. How could the man who vies in surveys with Albert Einstein for the title of “greatest physicist ever,” the man whom James Gleick has aptly designated “chief architect of the modern world,” have been so swept up in what looks to modern eyes like a medieval delusion? How could the ultimate scientist have been seemingly hornswoggled by a totemic psuedoscience like alchemy, which in its commonest rendering is described as the desire to transform lead into gold? Was Newton mad  perhaps made mad by exposure to mercury, as some have proposed? Was he greedy, or gullible, or stubbornly blind to the truth?