Firstly, as Professor Dasgupta made clear in his Review, nature and many of the ecosystem services it provides are often “mobile, silent and invisible”, and therefore incredibly complex to fully appreciate. We may understand the price of wood and some of the services provided by forests (such as climate regulation or flood prevention) but we will never understand all the interactions that exist within nature. Secondly, different social groups and individuals relate differently to nature, as the IPBES made clear in its recent report on the diverse ways of valuing nature.xxv For instance, a poor fisherman or an indigenous person may not be able to put a high price tag on the fish he catches or the forest she lives in, yet their entire livelihoods directly depend on the existence of specific ecosystems. In other words, nature does not have a fundamental value but rather means 6  Page 7 sur 12 different things to different people. Recognizing this diversity of values, at the global level, is key to enable its protection. We cannot say how much a seaside or a bird song represents. Thirdly, even if we could perfectly account for the points above (complexity and multiplicity of values), nature remains only very partially substitutable. This means that we risk underestimating the costs of losing ecosystem services. For instance, Professor Dasgupta provocatively but insightfully reminds us that if we only look at how much pollination contributes to agricultural outputs in highincome countries, we may end up with a very small percentage of GDP.
The improvement we have seen in the economy over the last year and the abovetarget inflation we have experienced point to the need to begin the process of withdrawing the very substantial level of monetary stimulus which was put in place to counter the big financial shocks we experienced in late 2008 and early 2009. Such a policy should not be a threat to the recovery. In my view it is the key to sustaining the recovery. It is the right response to an economy which is growing but experiencing persistent above-target inflation. It would reduce the risk of a future shock to confidence if current above-target inflation does become more deeply embedded and interest rates then need to rise more sharply to combat it. And it would provide more confidence to the public and the business community that the MPC takes its remit seriously and is determined to ensure that this recovery is built on the solid foundation of price stability. BIS Review 134/2010  13