Jean-Loup Amselle, an international anthropologist and ethnologist, Director of Study at the Ecole des Hautes études en Sciences Sociales, Paris, editor of the journal Cahiers d’études africaines, known by his work on issues of identity, mixing and multiculturalism, has just published (October 2013) a book that has as the title Psychotropics and is dedicated to the “ayahuasca fever in the Amazonian forest”. The Author’s intention, declared from the first pages and continually confirmed, is worth a long comment. His text seems important much more because of the problems, questions and demands it raises and by the positioning it takes in the broad field of relations between the West and the rest of the world, than by the ethnographic content it presents. In short: a wave of irrationalism would be spreading in the scientific, illuminist and rational West. This irrationalism would be quite consistent with the latest developments in contemporary capitalism, defined by Amselle as nomadic, or better, as shamanic and additive, to underline its ability of seduction, either symbolic or related to the consumption of psychotropic or hallucinogenic substances. To this nomadic capitalism (characterized by individualism, competition for all against all, cocooning and retreating of the individual on its own), the “psychotropic” would provide instruments of subjectivity perfectly in line with its demands. The more generally, according to the A. The new age, personal development, alternative therapies, etc., would help to put, and maintain, humans in compatible capital forms. Among other things, long-term tourism towards shamans and healers of the world's tropical areas.