Grob has written, “it will not be sufficient to adhere to strict standards of scientific methodology alone. We must also pay heed to the examples provided us by such successful applications of the shamanic paradigm.” Under that paradigm, the shaman/therapist carefully orchestrates “extrapharmacological variables” such as set and setting in order to put the “hyper-suggestible properties” of these medicines to best use. This is precisely where psychedelic therapy seems to be operating: on a frontier between spirituality and science that is as provocative as it is uncomfortable.

