In this article, we will cover the main anti-Keynesianviews and macroeconomic systems that arose in the post Keynesperiod as well as their fiscal and monetary policy guidelines. As isknown, the early Classical economists introduced amacroeconomic system based on the Quantity Theory and Say’sLaw resulting in automatic full-employment equilibrium; andfinally after 1929-1934 Great World Depression, the KeynesianSystem was introduced as a “revolution” (Keynesian Revolution)in theory and practice. As a result of the Keynesian policiesimplemented, European countries and the United States not onlygot over the Great World Depression but also in the yearsfollowing the World War II, they have observed a fast and stablegrowth for a long time. Moreover...