A few years ago, the late popular historian David McCullough published a biography of Wilbur and Orville Wright, inventors of the airplane. The book was deservedly successful, and I read it entirely for pleasure myself. The brothers were typical of their Northern European Protestant race: intelligent, soft-spoken, hard-working, plain almost to the point of austerity in their manner of living.Their father was in fact a Protestant minister, and they lived with him and their unmarried sister in a middle-class dwelling in Dayton, Ohio. Since there was no such thing as a paid position for people trying to invent a flying machine, they earned a modest living selling bicycles. It was the carefully managed proceeds from this small business that financed all their travels and experiments.