Serfdom is the status of peasants under feudalism, specifically relating to manorialism. It was a condition of bondage or modified slavery which developed primarily during the High Middle Ages in Europe and lasted in some countries until the mid-19th century.

Serfs who occupied a plot of land were required to work for the Lord of the Manor who owned that land, and in return were entitled to protection, justice and the right to exploit certain fields within the manor to maintain their own subsistence. Serfs were often required not only to work on the lord's fields, but also his mines, forests and roads. The manor formed the basic unit of feudal society and the Lord of the Manor and his serfs were bound legally, economically, and socially. Serfs formed the lowest social class of feudal society.

The decline of serfdom in Western Europe has sometimes been attributed to the Black Death, which reached Europe in 1347,, although the decline had begun before that date. Although serfdom became increasingly rare in most of Western Europe after the Renaissance, it grew strong in Central and Eastern Europe, where it had previously been less common (this phenomenon was known as "later serfdom").

Milton Friedman (July 31, 1912 – November 16, 2006) was an American economist, statistician, and author who taught at the University of Chicago for more than three decades. He was a recipient of the Nobel Memorial Prize in Economic Sciences, and is known for his research on consumption analysis, monetary history and theory, and the complexity of stabilization policy. As a leader of the Chicago school of economics, he influenced the research agenda of the economics profession. A survey of economists ranked Friedman as the second most popular economist of the twentieth century behind John Maynard Keynes, and The Economist described him as "the most influential economist of the second half of the 20th century…possibly of all of it."

Friedman's challenges to what he later called "naive Keynesian" (as opposed to New Keynesian) theory began with his 1950s reinterpretation of the consumption function, and he became the main advocate opposing activist Keynesian government policies. In the late 1960s he described his own approach (along with all of mainstream economics) as using "Keynesian language and apparatus" yet rejecting its "initial" conclusions. During the 1960s he promoted an alternative macroeconomic policy known as "monetarism". He theorized there existed a "natural" rate of unemployment, and argued that governments could increase employment above this rate (e.g., by increasing aggregate demand) only at the risk of causing inflation to accelerate. He argued that the Phillips curve was not stable and predicted what would come to be known as stagflation. Friedman argued that, given the existence of the Federal Reserve, a constant small expansion of the money supply was the only wise policy.

Friedrich August Hayek CH (German pronunciation: [ˈfʁiːdʁɪç ˈaʊ̯ɡʊst ˈhaɪ̯ɛk]; 8 May 1899 – 23 March 1992), born in Austria-Hungary as Friedrich August von Hayek, was an economist and philosopher best known for his defense of classical liberalism. In 1974, Hayek shared the Nobel Memorial Prize in Economic Sciences (with his political rival, Gunnar Myrdal) for his "pioneering work in the theory of money and economic fluctuations and... penetrating analysis of the interdependence of economic, social and institutional phenomena." He considered the efficient allocation of capital to be the most important factor leading to sustainable and optimal GDP growth, and warned of harms from monetary authority manipulation of interest rates. Interest rates should be set naturally by equilibrium between consumption of goods or capital stock.

Hayek is considered to be a major economist and political philosopher of the twentieth century. Along with his mentor Ludwig von Mises, he was an important contributor to the Austrian school of economic thought. Hayek's account of how changing prices communicate information which enable individuals to coordinate their plans is widely regarded as an important achievement in economics. He also contributed to the fields of systems thinking, jurisprudence, neuroscience and the history of ideas.