I learned two things that summer about driving in Yellowstone National Park: First, there were no guardrails as you zipped along the edges of the canyons. Second, the shadows in the valley might be hiding a herd of buffalo, so you needed to keep your foot hovering over the brake. That wide-open feeling of freedom and danger was just what I needed.

Do you have a lemon in your kitchen? Put this magazine down for a moment, go cut the fruit in half, and squeeze some juice into your mouth. Notice how you react. Don’t have a lemon? Try this little thought experiment: Imagine that you have one. Picture yourself slicing through the bright yellow rind, exposing the translucent fruit inside. See yourself holding it up, squeezing it, and letting a stream of tart juice splash onto your tongue. Can you feel yourself puckering and salivating—not in your mind’s eye, but in “real life”? Western thinkers have tended to draw a line between reality—that which we “actually” experience—and imagination, seen as a frivolous, dreamlike diversion. For millennia, though, spiritual contemplatives and artists have taken flights of fancy much more seriously and challenged the firmness of that line. And surprising recent advances in neuroscience, particularly in the field of brain scanning, have added support to their conviction that our imagination and sense of reality are closely intertwined.

A Meditation on Life and Death By Erica Brown SIMON & SCHUSTER With sensitivity, humor, and unflinching honesty, writer and educator Erica Brown explores how fear and denial of death can diminish quality of life for the dying and those they leave behind. In Happier Endings, Brown poses a probing question: If we know death is certain, then why do so many of us live as though dying is for other people?

The first time my yoga teacher encouraged me to go upside down into a headstand, I yelped. My outburst was just loud enough to let everyone in the class—especially me—know that I was petrified. Stiff as an ancient tree turned to stone, I had to be told to breathe. While some people give no thought to going upside down, it was a Herculean challenge for me. I practiced for four years before I felt comfortable going up away from a wall, unassisted. I’ve since learned that the poses I find most difficult, whatever they may be, have the richest rewards.