from Pilgrim at Tinker's Creek by Annie Dillard:
In summer I stalk. Summer leaves obscure, heat dazzles and creatures hide from the red-eyed sun, and me. I have to seek things out. The creatures I seek have several senses and free will; it becomes apparent that they do not wish to be seen. I can stalk them in either of two ways. The first is not what you think of as true stalking, but it is the via negativa, and as fruitful as actual pursuit. When I stalk this way I take my stand on a bridge and wait, emptied. I put myself in the way of the creature's passing, like spring Eskimos at a seal's breathing hole. Something might come; something might go. I am Newton under the apple tree, Buddha under the bo. Stalking the other way, I forge my own passage, seeking the creature. I wander the banks; what I find I follow, doggedly, like the Eskimos haunting the caribou herds. I am Wilson squinting after the traces of electron in a cloud chamber; I am Jacob at Peniel wrestling with the angel.