This is the first of a few blogs that I will write about asset bubbles and modern monetary theory (MMT). The point came up this week in a comment posted by Sean Carmody in response to my blog – Operational design arising from modern monetary theory. It was also raised in the current debate about MMT and debt-deflation, which I will return to on Sunday. The proposition is that if the the central bank maintains a zero target interest rate then lending rates will be so low that there will uncontrollable asset bubbles. As long as fiscal policy is used sensibly I disagree that a zero interest rate policy is destabilising.