Forsyth suggests that a “‘complete financial externality’…would aptly describe the Great Financial Crisis of 2007-09.” I don’t think so. That crisis, like many others, was “endogenous,” as my old friend, Hy Minsky, used to say—reflecting the internal dynamics of interacting leverage, inflated asset prices, moral hazard, and risk in the financial system. Central banks are part of the system, and its internal interactions are not above the system in some celestial role. If you are prone to believe in “the control asserted by central banks over economies,” recall the hapless announcement by central banks that they had created the “Great Moderation,” which proved instead to be the Great Bubble. Widespread belief that central banks are in control may be another endogenous risk factor.