MARK EPSTEIN WRITES: Yoga came to me as if out of a commercial, or maybe a series of commercials. Advertising companies know that a person has to hear about a new product from something like five different directions before desire for that product is kindled. It was like that for me with yoga. All of a sudden, a number of years ago, I began to hear about it wherever I turned, and, although I resisted (thinking that meditation was enough for me), after a while I could ignore it no longer.