{Central banks} have all chosen implicitly, if not in a more overt fashion, to set our capital and other reserve standards for banks to guard against outcomes that exclude those once or twice in a century crises that threaten the stability of our domestic and international financial systems.

I do not believe any central bank explicitly makes this calculation. But we have chosen capital standards that by any stretch of the imagination cannot protect against all potential adverse loss outcomes. There is implicit in this exercise the admission that, in certain episodes, problems at commercial banks and other financial institutions, when their risk-management systems prove inadequate, will be handled by central banks. At the same time, society on the whole should require that we set this bar very high. Hundred-year floods come only once every hundred years. Financial institutions should expect to look to the central bank only in extremely rare situations.

I am obviously referring to far more adverse outcomes than I was alluding to in my earlier remarks on the need for private risk-management systems to adjust for crises in their estimates of risk distributions. However, where that dividing line rests is an issue that has not yet been addressed by the international banking community. Clearly, to choose the distribution of risk-bearing between private finance and government is to choose the degree of moral hazard. I believe we recognize and accept it. Indeed, making that choice may be the essence of central banking.

 At a conference honoring Anna Schwartz