The New Thought Movement was an enormously popular late nineteenth-century spiritual movement led largely by and for women. Mary Baker Eddy's Christian Science is but one example of the fascinating range of these groups, which advocated a belief in mind over matter and espoused women's spiritual ability to purify the world. This work is the first to uncover the cultural implications of New Thought, embedding it in the intellectual traditions of nineteenth-century America, and illuminating its connections with the self-help and New Age enthusiasms of our own fin-de-sicle.