The physiocrats considered that François Quesnay had created a ‘new science’, political economy. They set themselves the task of celebrating this event by writing its history. It is to this end that, in 1768, Pierre Samuel Du Pont wrote De l'origine et des progrès et d'une science nouvelle. In the first pages of his essay, Du Pont attributed the foundation of the science of political economy to ‘three equally worthy friends of the inventor of the Tableau Économique: de Gournay, M. le Marquis de Mirabeau and M. le Mercier de la Riviere’. The latter two, Victor Riqueti de Mirabeau (1715–1789) and Paul-Pierre Lemercier de la Rivière (1719–1801), were the doctor's principal collaborators, but Jacques Vincent de Gournay died early, in June 1759, before physiocracy as a concept had emerged. As intendant of commerce, Gournay (1712–1759) was at the centre of a circle of writers and administrators in France in the 1750s. These men, all closely associated with commerce, were charged with translating and disseminating what they called the ‘science of commerce’. Gournay's circle shared some key elements with the physiocrats. For example, both groups considered competition to be the principal driving force for the creation and circulation of wealth. They were also both very critical of the guilds and favoured freedom in the grain trade. However, either from a theoretical or a political point of view, Gournay's circle was less homogeneous than the physiocratic movement. The science of commerce cannot be summarized as a body of doctrines because it was really the product of group discussions. In addition, most of the authors in Gournay's circle did not see ‘freedom’ and ‘property’ as being governed by the immutable laws of a transcendent ‘natural order’. In contrast to the ahistorical truths of the physiocratic order, which local and regional history and circumstances had to yield to, the science of commerce was characterized by an ongoing focus on realities, contingencies and local practices. This epistemological stance was the source of future debates between the followers of the two. For example, Gournay was aware of the need to reinforce the French monarchy's naval capacity, and he therefore defended the instigation of a Navigation Act and the colonial Exclusif.