You can tell thru-hikers when you see them on the trail. Though they come in many flavors, they all have a knowledge that cannot be achieved through scholarship but shows in their eyes and their stance and their weary smile. It is a knowledge that cannot find a person through windshields or sunglasses, or the barriers of fresh clothing and fragrance that surround us every day. It stalks them quietly as weeks of hiking struggle by and the fragile web of pleasantry is tattered by passing branches and swarming bugs. It infects their thoughts as hunger surpasses sex, boredom, weariness, and cleanliness. It pounces one day when hikers no longer see and smell and feel nature, but are nature, and realize that they are surrounded by savage beasts, and they are we.