The global financial crisis of 2008 caused a re-examination of many aspects of economic theory and policy, particularly with regard to financial innovation and regulation. This is as it should be; any discipline, in conception and practice, should be reviewed in the light of such a major shock. The ongoing economic and public health crisis caused by the spread of Covid-19 should also cause such a review. The lineaments of such a change in approach are already visible. For one, it is clear that concerns about the environmental impact of economic activity have hitherto remained marginal. But they need to