About the Contributor(s): Geo Widengren (1907-1996) was a Swedish Orientalist and scholar of religion. He concentrated on the religions of the ancient Near East, and specifically of Iran. He also studied Judaism, Islam, and religious phenomenology. Birger A. Pearson is Professor Emeritus of Religious Studies at the University of California, Santa Barbara, and Professor and Interim Director of the Religious Studies Program at the University of California, Berkeley.