Introduction : judging "schemes of oeconomy" -- Travelling knowledge in the "discerning age" : ethnography and Enlightenment -- "The most unscrupulous people on earth" : the paradox of China's commercial spirit -- "Your beggarly commerce!" China and international trade -- "The science of princes" : China's constitutional foundations -- "Duties of the sovereign" : civil and military successes and failures -- "Very ignorant reasoners" : China's science and technology -- Conclusion : prospects for the "stationary state".