QUOTE : Whatever the evolutionary precursors of drug use are, a permanently “drug-free” human culture has yet to be discovered. Like music, language, art, and tool use, the pursuit of altered states of consciousness is a human universal. With access to few alternatives, Siberian shamans imbibe reindeer and human urine to maximize the psychedelic yield of Amanita muscaria mushrooms (the metabolite that is excreted may be stronger than the substance initially ingested); on nearly the opposite side of the world, New Zealanders party with untested “research chemicals” synthesized by Chinese chemists. Drug use spans time and culture. It is a rare human who has never taken a drug to alter her mood; statistically, it is non-users who are abnormal. Indeed, today, around two thirds of Americans over 12 have had at least one drink in the last year, and 1 in 5 are current smokers. (In the 1940s and ’50s, a whopping 67% of men smoked.) Among people ages 21 to 25, 60% have taken an illegal drug at least once—overwhelmingly marijuana—and 20% have taken one in the past month. Moreover, around half of us could suffer from physical withdrawal symptoms if denied our daily coffee. While Americans are relatively prodigious drug users—topping the charts in the use of many substances—we are far from alone in our psychoactive predilections.