Among the various kinds of occultism popular during the Russian Silver Age (1890-1914), modern Theosophy was by far the most intellectually significant. This contemporary gnostic gospel was invented and disseminated by Helena Blavatsky, an expatriate Russian with an enthusiasm for Buddhist thought and a genius for self-promotion. What distinguished Theosophy from the other kinds of "mysticism"--the spiritualism, table turning, fortune-telling,...