Devereux's interpretation of indirect archaeological evidence of psychedelic use in ancient western Europe often comes across as highly speculative. But it's an intriguing look at the kinds of clues "cognitive archaeologists" use to reconstruct long-lost behavior, and in any case the brisk global tour of long-exploited psychoactive plants leaves no doubt of the intimate relation between these drugs and most human culturesthe notable exception being our own. From early Eurasia (the familiar red-capped fly agaric mushroom and the legendary soma) to Africa (ibogaine and khat), through the arcane traditions of Native Americans and the plant lore of "witchcraft," natural hallucinogens have been an integral part of shamanic religions' belief in a higher plane. Devereux, constantly emphasizing the role of context in any psychedelic experience, takes pains to show that hallucinogens were usually strictly regulated aspects of a coherent culture's rites. Thus, while not simply proselytizing for the indiscriminate use of psychedelics, Devereux is fanatically keen to demonstrate what modern Western culture is missing out on in its underappreciation of this history (as well as of expanded consciousness itself). Because of this underappreciation, much such study has been performed outside of mainstream anthropology and archaeology. As a consequence, perhaps, while Devereux's book is a handy summary of this research, much information seems sketchily documented, when it is not outright unexplained assertion.
Devereux's claims for the true insights afforded by psychedelics (including prediction and remote viewing) invite some skepticism, too. But he shows that judgments would be better made in a climate of rational inquiry into the obviously basic human predilection for altered consciousness.