George Malcolm: half white, half black, with messy tousled hair, rumpled and tugged between kind of curly and extremely curly. Once, a year or so before, he'd been at our house and he'd pulled out a lock of his hair and used it to teach me about eddies and helixes. It's a circular current into a central station, he'd explained, giving me one to hold. I pulled on the spring. Nature is full of the same shapes, he said, taking me to the bathroom sink and spinning on the top and pointing out the way the water swirled down the drain. Taking me to the bookshelf and flipping open a book on weather and showing me a cyclone. Then a spiral galaxy. Pulling me back to the bathroom sink, to my glass jar of collected seashells, and pointing out the same curl in a miniature conch. See? he said, holding the seashell up to his hair. Yes! I clapped. His eyes were warm with teaching pleasure. It's galactic hair, he said, smiling.At school, George was legendary already. He was so natural at physics that one afternoon the eighth-grade science teacher had asked him to do a preview of the basics of relativity, really fast, for the class. George had stood up and done such a fine job, using a paperweight and a yardstick and the standard-issue school clock, that the teacher had pulled a twenty-dollar bill from his wallet. I'd like to be the first person to pay you for your clarity of mind, the teacher had said. George used the cash to order pizza for the class. Double pepperoni, he told me later, when I'd asked.