Book excerpt: Secret Wisdom is a profusely illustrated exploration of the Western Mystery tradition and its development through the centuries. Aspects of the tradition can be seen to have influenced the growth of Christianity, the culture of the Renaissance and even the great discoveries of astronomy and experimental science. The book explains this hidden current of knowledge and demonstrates how profoundly important it has been, subtly yet strongly influencing our culture in a variety of ways. Features include: . How the tradition of secret knowledge was founded in ancient Greece, in the rites of Demeter at Eleusis and the Orphic Mysteries. .The rise of the Greek philosophers, who reveal the real meaning of astrology and the purpose of humanity. . What Christ's teachings absorbed from the Mysteries. . How the Persians preserved the tradition, developing sophisticated techniques of alchemy, astrology and magic. . The revelation of the knowledge during the Renaissance, as ancient manuscripts are discovered and translated. .'Learned magic' and its role in shaping the perceptions of famous scientists and inventors. . The concept of ideal societies, and their reflection of secret understanding. . The relationship between alchemy and experimental science. . The expression of the Mysteries through art and literature.