However, the premises of Keynes’s work have since been challenged by neoclassical and supply-side economics and the Austrian School. Another challenge to Keynesian thinking came from his colleague Piero Sraffa and subsequently from the Neo-Ricardian school that followed Sraffa. In Sraffa's highly technical analysis, capitalism is defined by an entire system of social relations among both producers and consumers, but with a primary emphasis on the demands of production. According to Sraffa, the tendency of capital to seek its highest rate of profit causes a dynamic instability in social and economic relations. Supply-side economics Supply-side economics is a school of macroeconomic thought that argues that economic growth can be most effectively created by lowering barriers for people to produce (supply) goods and services, such as adjusting income tax and capital gains tax rates and by allowing greater flexibility by reducing regulation. Consumers will then benefit from a greater supply of goods and services at lower prices. The term "supply-side economics" was thought for some time to have been coined by journalist Jude Wanniski in 1975, but according to Robert D. Atkinson's Supply-Side Follies the term "supply side" ("supply-side fiscalists") was first used in 1976 by Herbert Stein (a former economic adviser to President Nixon) and only later that year was this term repeated by Jude Wanniski. Its use connotes the ideas of economists Robert Mundell and Arthur Laffer. Today, supply-side economics is often conflated with the politically rhetorical term "trickle-down economics", but as Jude Wanniski points out in his book The Way The World Works trickle-down economics is conservative Keynesianism associated with the Republican Party. Typical policy recommendations of supply-side economics are lower marginal tax rates and less regulation. Maximum benefits from taxation policy are achieved by optimizing the marginal tax rates to spur growth, although it is a common misunderstanding that supply side economics is concerned only with taxation policy when it is about removing barriers to production more generally. Many early proponents argued that the size of the economic growth would be significant enough that the increased government revenue from a faster-growing economy would be sufficient to compensate completely for the short-term costs of a tax cut and that tax cuts could in fact cause overall revenue to increase. Neoclassical economics and the Chicago School Today, the majority academic research on capitalism in the English-speaking world draws on neoclassical economic thought. It favors extensive market coordination and relatively