One of the most significant and vital eras in the history of ethnobotany coincided with the spice trade during the European Age of Discovery, which began in the 15th century with the Portuguese exploration of Africa and wound down in the late 17th century when cultivation of spices expanded throughout the tropical world. Nonetheless, the trade in spices by Arab, Chinese, and Indian merchants commenced long before European involvement. Botanical bounty like cinnamon (Cinnamomum spp., Lauraceae), cloves (Syzygium aromaticum, Myrtaceae), nutmeg (Myristica fragrans, Myristicaceae), and black pepper (Piper nigrum, Piperaceae) were moving from Southeast Asia and India to the Middle East long before the early 1400s when Prince Henry the Navigator (1394–1460) kickstarted Portuguese exploration of tropical regions.

In his newest book, Psychonauts, he casts his net still wider, endeavoring to explain how experimentation with psychoactive drugs by a wide and diverse array of Westerners directly contributed to the birth of psychology and helped expand the frontiers of art, medicine, music, and science. In these pages, one encounters Honoré de Balzac, Charles Baudelaire, Samuel Taylor Coleridge, Wade Davis, Humphry Davy, Thomas De Quincey, Benjamin Franklin, Sigmund Freud, Johann Wolfgang von Goethe, Robert Hooke, Alexander von Humboldt, Thomas Huxley, Immanuel Kant, Isaac Newton, Joseph Priestley, Henry Rusby, Joe Rogan, Mike Tyson, and Andrew Weil — all before the second chapter.

“This book will be devoured by all Nabhanophiles and should be read by all those interested in food, culture, conservation, botany, and the worlds around them. So chock full of great ideas, penetrating insights, and unforgettable landscapes, it should be savored slowly like the fine feast it is!”—Economic Botany.