The historian Charles A. Beard identified Federalist No. 10 as one of the most important documents for understanding the Constitution. In his book "An Economic Interpretation of the Constitution of the United States" (1913), Beard argued that Madison produced a detailed explanation of the economic factors that lay behind the creation of the Constitution. At the outset of his study, Beard writes that Madison provided "a masterly statement of the theory of economic determinism in politics" (Beard 1913, p. 15). Later in his study, Beard repeated his point, providing more emphasis. "The most philosophical examination of the foundations of political science is made by Madison in the tenth number," Beard writes. "Here he lays down, in no uncertain language, the principle that the first and elemental concern of every government is economic" (Beard 1913, p. 156).