I’m loading my backpack, a sleek urban model that Thoreau would never own, when I decide to do something out of character. I tuck my smartphone into the desk drawer and step outside without it. It takes only a few minutes for the withdrawal symptoms to manifest: clammy skin, increased heart rate. It’s not that I feel naked without my phone. Naked I could handle. I feel as if I’ve departed on my walk without my liver or some other vital organ. Yet I soldier on.