Essai is considered the first complete treatise on economics, with numerous contributions to the science. These contributions include: his cause and effect methodology, monetary theories, his conception of the entrepreneur as a risk-bearer, and the development of spatial economics. Cantillon's Essai had significant influence on the early development of political economy, including the works of Adam Smith, Anne Turgot, Jean-Baptiste Say, Frédéric Bastiat and François Quesnay.