Includes bibliographical references (pages 339-345) and index.

In this unique blend of history, science and memoir, the author examines and experiences three plant drugs--opium, caffeine and mescaline--from several very different angles and contexts, exploring the powerful human attraction to psychoactive plants.

Of all the things humans rely on plants for--sustenance, beauty, fragrance, flavor, fiber--surely the most curious use of them is to change consciousness: to stimulate or calm, fiddle with or completely alter, the qualities of our mental experience. Take coffee and tea: people around the world rely on caffeine to sharpen their minds. We don't usually think of caffeine as a drug, or our daily use as an addiction, because it is legal and socially acceptable. So then what is a "drug?" And why, for example, is making tea from the leaves of a tea plant acceptable, but making tea from a seed head of an opium poppy a federal crime? Michael Pollan dives deep into three plant drugs -- opium, caffeine, and mescaline -- and throws the fundamental strangeness, and arbitrariness, of our thinking about them into sharp relief. Based in part on an essay written more than 25 years ago, this groundbreaking and singular consideration of psychoactive plants, and our attraction to them through time, holds up a mirror to our fundamental human needs and aspirations, the operations of our minds, and our entanglement with the natural world.