I’m headed with friends to the Kalalau Valley on Kauai’s Nā Pali Coast. My friend Isaac has boated in with most of our group’s gear. Jenny and I, carrying granola bars and sleeping bags and sarongs and books like “State of Wonder” by Ann Patchett and “Waking up in Eden” by Lucinda Fleeson and emergency supplies like Band-Aids and alcohol, hike the eleven miles of tropical trail that lead to the valley. I’ll stay six days. Jenny and Isaac wil...