Reincarnation is the religious or philosophical concept that the soul or spirit, after biological death, begins a new life in a new body that may be human, animal or spiritual depending on the moral quality of the previous life's actions. This doctrine is a central tenet of the Indian religions and is a belief that was held by such historic figures as Pythagoras, Plato and Socrates. It is also a common belief of other religions such as Druidism, Spiritism, Theosophy, and Eckankar and is found in many tribal societies around the world, in places such as Siberia, West Africa, North America, and Australia. Although the majority of sects within the Abrahamic religions of Judaism, Christianity and Islam do not believe that individuals reincarnate, particular groups within these religions do refer to reincarnation; these groups include the mainstream historical and contemporary followers of Kabbalah, the Cathars, and the Shia sects such as the Alawi Shias and the Druze and the Rosicrucians. The historical relations between these sects and the beliefs about reincarnation that were characteristic of Neoplatonism, Orphism, Hermeticism, Manicheanism and Gnosticism of the Roman era, as well as the Indian religions has been the subject of recent scholarly research. In recent decades, many Europeans and North Americans have developed an interest in reincarnation. Contemporary films, books, and popular songs frequently mention reincarnation. In the last decades, academic researchers have begun to explore reincarnation and published reports of children's memories of earlier lives in peer-reviewed journals and books.