"When Isaac Newton died at 85 without a will on March 20, 1727, he left a mass of disorganized papers—upwards of 8 million words—that presented an immediate challenge to his heirs. Most of these writings, on subjects ranging from secret alchemical formulas to impassioned rejections of the Holy Trinity to notes and calculations on his core discoveries in calculus, universal gravitation, and optics, were summarily dismissed by his heirs as "not fit to be printed." ... In The Newton Papers, Sarah Dry divulges the story of how this secret archive finally came to light—and the complex and contradictory man it revealed."
"After examining letters written by Newton's acquaintances, the French astronomer Jean-Baptiste Biot claimed in 1822 that Newton had suffered a "mental derangement" in his late 40s—and that his writings on alchemy and theology were products of his madness."