Our species has spent almost all of its existence on the African savanna, surrounded by trees, water, and sky. The world in which most of us spend our time nowadays is unnatural and can corrode the spirit. Even a small dose of nature elevates our mood. But accept no substitutes! Psychologist Peter Kahn Jr. put 50-inch high-definition TVs into windowless offices of faculty and staff members at the University of Washington in Seattle, then streamed in a live view of a natural scene. It turned out that these HDTVs did nothing for the participants’ physiological stress response. What worked? A window with a view of real greenery. My guess is that even a view of a humdrum landscape, like the parking lot of an office building, is more emotionally satisfying than the most beautiful travel poster.