Mary Baker Eddy was born in 1821 in Bow, New Hampshire, a small hardscrabble farming community. Fifty-four years later, she launched the wildly popular religion Christian Science when she published Science and Health With Key to the Scriptures (1875). Her text argued that God had created a perfect sinless, illness-free world and men and women needed only to recognize that perfection to achieve the good life. Forging the tenets for a new religion was a remarkable accomplishment for anyone, but especially for a thrice married, divorced, and widowed middle-aged woman born into poverty. Mark Twain called her “the most interesting woman that ever lived.”

The youngest of six children born to Mark and Abigail Baker, Mary Baker was a sickly, difficult child. She suffered from headaches, an eating disorder, and bouts of unexplained “pain and weakness.” She rebelled, screaming and falling to the floor where she would lay for hours seemingly unconscious. Her father, a Calvinist, sternly told her that pain and illness were a part of God’s plan. He also pampered her, building a crib large enough to accommodate a growing adolescent girl and hiring a boy to rock her in it whenever she felt ill or anxious. Kept from attending school, Mary plunged into a self-education program. She read religious and philosophical texts and learned some Latin. She made use of her newly acquired knowledge to dispute a minister’s sermon justifying predestination, though she later accepted the tenet and owned the covenant in 1838.

Her grudging acceptance of Calvinism brought her neither happiness nor good health. As it did for most nineteenth-century Americans, death and disease pockmarked her life. Her favorite brother Albert died in 1841, at age 31. Two years later, when she was 22, Mary married George Washington Glover. Just six months after the couple settled in Charleston, South Carolina, George died from yellow fever. Mary, alone and pregnant, returned home where she gave birth to her son. Exhausted and depressed, she stayed in bed for months. In 1849, Mary’s mother, her only source of love, died. Three weeks later her fiancé, John Bartlett, succumbed to disease. The following year her father remarried and, according to Eddy’s later account, he insisted her 4 year-old-son be sent away. “I had no training for self-support,” she wrote defensively, adding without explanation that Daniel Patterson, an itinerant dentist she had married in 1853, “consummated a plot” for keeping her away from her son.

There were other problems. Patterson’s infidelity and Mary’s ongoing search for good health led the couple to separate. (She divorced Patterson in 1873 and married Asa Eddy in 1877.) She experimented with popular health fads: Sylvester Graham’s vegetarianism, hydrotherapy, mesmerism, hypnosis, homeopathy, and spiritualism. For four years she conducted séances, received spirit communications, and boarded with spiritualists in and around Boston. Nothing she tried restored her health. Finally, in 1862 she became a patient and later a partner of Phineas Parkhurst Quimby, a healer steeped in Protestant theology and science, a combination leading him to conclude that a patient’s thoughts and illness were linked. “P.P. Quimby,” Mary wrote in a Portland newspaper, “rolls away the stone from the sepulcher of error and health is the resurrection.”

In 1866, shortly after Quimby’s death, Eddy fell on an icy sidewalk and suffered a painful back injury. As she later told the story, doctors declared there was no hope of recovery. On the third day, however, she picked up her Bible, opened it to Matthew 9: 2, and read an account of Jesus healing the sick. She recovered instantly and grasped the central idea of what became a new religion: Christian Science. She spent the next three years fleshing out her insight. She borrowed heavily – some say plagiarized – Quimby’s ideas. She incorporated bits of Eastern religion. But her argument remained familiar to Christians: healing could occur only when a person understood that God had created a perfect spiritual world in which sin, disease, and death did not exist. God is perfect, humankind is God’s creation and therefore, despite appearances to the contrary, mankind is perfect. The power to heal is available to everyone who follows the scientific principles revealed in the Bible and explained in Science and Health. The principles she laid out were: one, the material world and all its living inhabitants and innate elements are not reality; and two, all disease is rooted in the human mind’s blindness to God’s presence and is the cause of all disease. Therefore, drugs do not heal because they treat illness as a reality. Only the spiritual world is real and free of imperfections.

It was on this rock that Mary Baker Eddy created the Church of Christ, Scientist. She built the magnificent Mother Church in Boston and bound all subsequent church leaders to follow her instructions about church governance, finances, and, most importantly, about healing. She insisted that every account of an alleged healing be collected and published as a way of touting individual members’ claims of their conquest of illness and of providing a mountain of anecdotal evidence of the church’s success and legitimacy. Although the emergence since the 1940s of highly trained physicians and life-saving drugs have cut into the number of adherents to Christian Science, the church still successfully plays on many people’s distrust of modern medicine. Tragically, in the 1980s and 1990s scores of American children died when their parents rejected modern science and tried to heal their youngster’s illnesses through spiritual healing alone.