In The Subtle Body, Stefanie Syman tells the surprising story of yoga's transformation from a centuries-old spiritual discipline to a multibillion-dollar American industry.

Yoga's history in America is longer and richer than even its most devoted practitioners realize. It was present in Emerson's New England, and by the turn of the twentieth century it was fashionable among the leisure class. And yet when Americans first learned about yoga, what they learned was that it was a dangerous, alien practice that would corrupt body and soul.

A century later, you can find...