Monetarism is an economic theory that revolves around the money supply and the ability of a central bank to regulate the economy by controlling its money supply. Monetarists believe that a healthy economy is one with a money supply that is sufficient to meet the needs of its citizens, but not too great to cause inflation. This belief is based on the fact that an oversupply of money is inflationary, while an undersupply of money is recessionary.

Monetarists argue that monetary policy is the most effective tool that governments can use to manage the economy. They believe that the government should focus on maintaining a steady rate of growth in the money supply, and that it should ignore short-term changes in interest rates and business cycle fluctuations. This doctrine of stable money supply is known as the Monetary Base theory.

Monetarists argue that money supply should be adjusted according to changes in the nation's economic environment, such as shifts in spending and investment. They believe that changes in the money supply should be implemented in a slow and steady manner to avoid causing instability in the economy. For example, if there is strong evidence of an economic downturn, then the government should cut interest rates or increase the money supply to avoid an economic slowdown.

Famous monetarists include Nobel Laureate Milton Friedman, former Federal Reserve Chairman Alan Greenspan, and former Prime Minister Margaret Thatcher. They have argued that monetary policy is the only way to safely manage the economy without damaging its long-term prospects.

Monetarism is not without its detractors. Some economists, for example, argue that a stable money supply does not guarantee full employment or economic growth. Monetarists also argued that government has no reason to intervene in business decisions, a notion that has since been rejected by many policymakers.

Ultimately, monetarism is an important school of thought that has shaped the way modern governments and central banks manage their economies. Although its methods may be viewed as overly simplistic, the underlying principles of monetarism remain relevant today as governments seek to maintain stable prices and economic growth in the face of changing economic conditions.