Quesnay, Francois, keh NAY, fron SWAH (1694-1774), was a French economist who made some of the earliest contributions to the development of economics. He headed a group of economic writers called the physiocrats. The physiocrats believed that natural laws direct economic activity, and they tried to discover these laws. They devised early forms of economic models, charts or sets of formulas showing the relationships between various parts of a nation's economy.