"The central banks cannot control interest rates. That's a mistake. They can control a particular rate, such as the Federal Funds rate, if they want to, but they can't control interest rates."

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What central banks can control is a base and one way they can control the base is via manipulating a particular interest rate, such as a Federal Funds rate, the overnight rate at which banks lend to one another. But they use that control to control what happens to the quantity of money. There is no disagreement.

— Milton Friedman