Historians long explained Britain's early industrialization by pointing to its abundant coal and the ingenuity of a few inventors. A revisionist account gives more weight to the structure of wages. Because labor in eighteenth-century Britain was unusually expensive relative to the cost of energy, employers had a strong incentive to replace workers with fuel-burning machines—an incentive far weaker in economies where labor was cheap. On this reading, the celebrated inventions were less the spark of the revolution than its predictable result: entrepreneurs invested in mechanization precisely where the arithmetic of high wages and cheap coal made it profitable. Critics of the wage thesis object that it understates the role of scientific culture and secure property rights, without which the machines might never have been built or protected. The debate has not been settled, but it has usefully redirected attention from the lone genius to the economic conditions that made his labors worth pursuing.