The Federal Reserve and other central banks manipulate interest rates every day, James Grant of Grant’s Interest Rate Observer told CNBC’s “Closing Bell” on Thursday. “The Fed is in the business of trying to manipulate markets, the macro economy, interest rates, unemployment and inflation through various monetary means, including the twisting around of yield curves and interest rates,” Grant said. Grant added, “The Federal Reserve fixes rates on principle. They have ‘operation twist’ that manipulates the credit markets. They have quantitative easing that manipulates bond yields.”