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As this discussion illustrates, the literal-but-symmetric interpretation of the MINIMAX approach to robust monetary policy would imply very ‘activist’ policy responses in the face of uncertainty. In this framework, from having their foot to the floor with the monetary accelerator, policymakers might have to switch in short order to stamping on the monetary brake. Unsurprisingly, on my reading, that characterisation also finds little sympathy in policymaking circles. In the interests of avoiding tail outcomes, such activism threatens to induce volatility into monetary policy, financial markets, the economy and inflation in other circumstances, which is both costly and hard to communicate. But the research on monetary policy and uncertainty as a whole has influenced the discussion and conduct of policy in practice. I would pick out a number of lessons that have been drawn.  The magnitude and evolution of uncertainty and risk can, do and should influence monetary policy decisions.  Not all uncertainty is the same. The way uncertainty influences monetary policy decisions depends on the circumstances and the nature of the uncertainty – its source, its persistence, its magnitude – that is being faced  Monetary policy should not be paralysed in the face of uncertainty. If policymakers were to wait until all uncertainty is resolved before taking decisions, they would wait forever.  At the same time, there is no general rule that says policy responses should either be attenuated or more activist in the face of uncertainty.