at things." Weil's undergraduate thesis was titled "The Use of Nutmeg as a Psychotropic Agent", specifically, on the narcotic properties of nutmeg, inspired by a class with David McClelland, chair of the Department of Social Relations, and a former director of Harvard's Center for Research in Personality. In 1964, he graduated cum laude with a B.A. in biology. Medical training Weil entered Harvard Medical School, "not with the intention of becoming a physician but rather simply to obtain a medical education." He received a medical degree in 1968, although "the Harvard faculty ... threatened to withhold it because of a controversial marijuana study Weil had helped conduct" in his final year. Weil moved to San Francisco and completed a one-year medical internship at Mount Zion Hospital in 1968–69. While there, he volunteered at the Haight-Ashbury Free Clinic. Weil went on to complete one year of a two-year program at NIH, resigning due to "official opposition to his work with marijuana". Career Following his internship, Weil took a position with the National Institute of Mental Health (NIMH) that lasted approximately one year, to pursue his interests in research on marijuana and other drugs; during this time he may have received formal institutional permission to acquire marijuana for the research. Weil is reported to have experienced opposition to this line of inquiry at the NIMH, to have departed to his rural northern Virginia home (1971-1972), and to have begun his practices of vegetarianism, yoga, and meditation, and work on writing The Natural Mind (1972). At the same time, Weil began an affiliation with the Harvard Botanical Museum that would span from 1971 to 1984, where his work included duties as a research associate investigating "the properties of medicinal and psychoactive plants". His interests led him to explore the healing systems of indigenous people, and with this aim, Weil traveled throughout South America and other parts of the world, "collecting information about medicinal plants and healing", from 1971 to 1975, as a fellow for the Institute of Current World Affairs. In 1994, Weil founded the Arizona Center for Integrative Medicine at the University of Arizona College of Medicine in Tucson, Arizona, where he serves as its director. Andrew Weil is the founder of True Food Kitchen, a restaurant chain serving meals on the premise that food should make you feel better. There are currently 32 restaurants in the chain. View of conventional medicine