There's a reason we pause at the vista overlook and be quiet for a second. The wilderness, or simply being outside in the natural world, provides us with a psychological reboot. It declutters our minds, washes off the guff, gives us a chance to see and feel ourselves as expansively as the Tunnel Overlook in Yosemite Valley. But the process is different, and in some ways, more powerful than the benefits we get from sleep. The Little Book...