Even with several tablespoons of peyote in me, by 3 in the morning I'm fading. For almost six hours I have been sitting in a tepee in the Navajo Nation, the largest Indian reservation in the United States, with 20 Navajo men, women, and children. They belong to the Native American Church, which has 250,000 members nationwide. Everyone except the four children has eaten the ground-up tops, or buttons, of peyote, Lophophora williamsii. U.S. law classifies the squat cactus and its primary active ingredient, mescaline, as Schedule 1 substances, illegal to sell, possess, or ingest. The law exempts members of the Native American Church, who revere peyote as a sacred medicine.
A barrel-chested man wearing a checked shirt and cowboy boots stands over the cedarwood fire and murmurs a prayer in Diné, the Navajo language. As this roadman, or leader of the service, sprinkles sage on the coals, my eyelids close. I smell the sage and hear it hiss, and I see the roiling geometric patterns, called form constants, generated by compounds such as mescaline. Then the balding white man on my right nudges me and tells me to keep my eyes open. The Navajo might be offended, he whispers, if they think I have fallen asleep. Later, he shakes his head when I lean on an elbow to relieve the ache in my back. Too casual, he says. My guide to the etiquette of peyote ceremonies is John Halpern, a 34-year-old psychiatrist from Harvard Medical School. For five years he has been coming here to the Navajo Nation—27,000 square miles of sage-speckled desert stretching from northern Arizona into New Mexico and Utah—to carry out a study of peyote. Funded by the National Institute on Drug Abuse, the study probes members of the Native American Church for deficits in memory and other cognitive functions. Halpern has brought me here to help me understand him and his mission, which is to provoke a reconsideration of the pros and cons of hallucinogenic drugs, commonly referred to as psychedelics.