Discussions around Science, Religion and Art break down unless the fourth factor, Magic, is recognised. Magical thought is described and contrasted with Science, Art and Religion. The dynamic relationship between them is explained. Modern magic and its role in the 21st century is outlined with respect to practices ranging from ritual magic, through alchemy to New Age therapies. Specific topics include: secrecy, initiation, sacrifice, cyber-animism, Crowleyanity, morality, pseudo-science, demonology, deity, miracles and divination.