Most books of history are stories of becoming. They wrestle with the difficult question of how we are to understand the creation of the new and its relation to what has come before. Breen's book does so with elegance and artistry. Entirely concerned with comprehending novelty, experimentation, and transmutation, this meticulously crafted study takes readers to the Age of Reason to demonstrate that this could well be renamed as the title of the book. A skillful historian, Breen circumvents easy paths. Instead of merely documenting the “discovery” of plants, animals, or minerals with psychoactive properties, or tracing the networks of knowledge and trade that made possible their circulation among continents, the author offers an ambitious and complex analysis of changing epistemologies and shifting paradigms regarding intoxication, healing, spirituality, credibility, and erudition.

Organized in two parts of three chapters each, the book focuses on the Portuguese and British empires, respectively. The reason, Breen explains, is because drogas were “the most unique and valuable of the commodities to which the Portuguese could lay claim” (96). Lusophone slave traders, scientists, and agents of empire were pioneering drug merchants. They established the foundations of a global trade that their British counterparts eventually developed further. Moving between colonies and metropoles—from Luanda to Brazil, from Lisbon to London—and using a diverse collection of sources—paintings, treatises, travelogues, and Inquisition records—Breen brings back to life a surprisingly wide array of characters whose adventures, enterprises, and failures allow the author to revive an old conversation among drug historians about the drug trade as an intrinsic aspect of modernity and globalization.

Bridging the fields of history of medicine, pharmacology, religion, and drugs, Breen makes three important points. First, what constitutes a drug is “in a state of constant change” (190), swept by the epistemological winds of its times. The “invention” of drugs (notice that the author rejects the term “discovery”) was a long-term process of experimentation paved with conflict, confusion, difference, and erasure. For centuries, a multiplicity of actors engaged in a series of trials and errors to define the divide between cure and curse, medicine and food, poison and intoxicant. This process involved the plantation, the backlands, the slave entrepôt and ship, and the surgeon's table as much as the chambers of the apothecary, the pharmacist, and the scientist. The result was the gradual and always contested fetishization and commodification of mind-altering plants and substances.

Second, although drugs were part and parcel of an ever-growing trade in “exotic” material goods, they were the most challenging ones to appropriate and commodify. Their occult qualities and association with non-European cultures and non-Christian spiritual practices made drugs “a kind of advance guard for both the allure and the dangers of global trade” (6). Breen's insightful analysis of the bewilderment that Europeans felt toward psychoactive products hailing from the tropical and subtropical areas of the world, due to their lack of mental categories to make sense of new forms of intoxication, constitutes one of the strongest sections of the book. This restricted “normative model of intoxication” (131) meant that globalizing a specific product depended on its “cultural translatability” (141). Naturalists, philosophers, and scientists played that role, helping turn drugs from curiosities into commodities, and from commodities into objects of scientific interest. Their acts of epistemological alchemy disassociated drugs from their non-European origins and the racialized subaltern groups that produced, harvested or consumed them—even from nature itself. Over time, a split emerged between the illegal “raw” versions and the chemically “processed” ones (176).

Third, this divide is still alive and buoyant in today's distinction between licit pharmaceuticals and illicit drugs, and legal and illegal systems of distribution and control. The epistemological, commercial, and social structures of colonialism and imperialism, and the religious antagonisms and notions of racial hierarchy that sustained them, provide the general frameworks for the vilification of certain drugs and the celebration of others as scientific miracles. The deep-seated splinter that the age of intoxication produced in the modern normative model of psychoactivity is the bedrock of our current drug policies.

At a time when the global drug trade, both licit and illicit, has become an important battleground for state and non-state actors to exercise greater control over bodies and minds, this fascinating tale “of missed opportunities and good intentions gone awry” (151) is rich in significance. Decades ago, psychiatrist and historian David Musto alerted us about the social and cultural importance of our long-term affair with drugs, and the dangers of forgetting its lessons. Breen takes us to a similar conclusion on the “failure of memory” in both the academy and society (188). One only hopes that this provocative and creative book that places intoxicants and the actions and ideas of dozens of anonymous people at the center of modernity will be a reminder of the lessons of the past, a cue widely read across disciplinary boundaries and beyond.