In an investigation into the nature and causes of the wealth of nations. Smith has analyzed the origin of the prosperity of countries like England and the Netherlands. Develop economic theories of the division of labor, the market, the currency, the nature of wealth, the price of goods, wages, profits and capital accumulation. Examine different systems of political economy, in particular mercantilism and physiocracy; also develops the idea of a natural order. This "system of natural liberty," as Smith calls it, is the result of the free exercise of individual interest without intending to do that successfully benefit the common good at solving problems and meeting needs through free enterprise, the free competition and free trade.