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. should we conclude that we can live without pollinators and without food? that would be foolish and dangerous of course. we therefore need to understand how shocks in one sector can ( and will, in the case of biodiversity loss ) greatly affect the output of other sectors. and the current gas crisis in europe is an example of the fact that we have not sufficiently thought about this. hence, what we need to understand as central bankers is that the best risk mitigation strategy is to do everything in our power, early enough, to ensure that we remain within planetary boundaries. the dasgupta review indicates ( in chapter 17, dedicated exclusively to the financial sector ) that failing to do so will lead to systemic environmental risks known as “ green swans ” xxvi. elsewhere in the review, he also reminds us that the loss of nature ( of natural capital ) is only very partially substitutable with labor or manufactured capital. beyond monetary valuations of ecosystem services what we truly need to understand is that as living creatures, we are “ embedded in nature ”, to quote professor dasgupta again. however, it is pretty clear that our socioeconomic system is currently disembedded from nature : it takes much more from it than what nature can provide us. in 1823, french economist jean - baptiste say famously said that natural resources are infinite because if they were not, we would not be able to obtain freely. he deducted from this that the still emerging economic discipline did not need to be concerned with the value of natural resources. page 8 sur 12 today, we can see how problematic this statement is. we do not only need to make these resources ( and ecosystem services ) visible to the economic discipline ( including through price signals ), we also need to engage in a self - critical assessment to understand how the discipline may need to revisit some

ratios close to 100 %. on the other, emerging economies, with high savings, low debt ( around 30 % gdp on average ) and bis central bankers ’ speeches less absorption capacity. our common prosperity will therefore depend on our ability to create stable channels of financial intermediation between those two parts of the world. that, in turn, will crucially depend on the existence of assets that can be considered safe stores of value. but, as i have argued from the start, public debt may not be able to play that role to the same extent as before. the ultimate safe asset, therefore, could be the currency itself. markets will trust currencies that are managed with one overriding priority : preserving price stability and the intrinsic value of the currency unit. on this fundamental basis, we can look at the future of the euro with realistic optimism. i see the recent decision by the swiss central bank to peg the swiss franc to the euro as an illustration of this conviction. * * * * a few words now on the french banking sector. first, banks have been hit in all advanced economies by the downward revision of growth prospects. this reaction can be explained by the fact that slower growth means lower profits, thus lower dividends. at the same time, banks are required to build additional capital buffers, which further constrain their pay - out ratio. so dividend prospects are doubly affected and that explains why share prices are reacting to negative news on growth. this movement has been more pronounced for french banks which are suffering from two specific vulnerabilities, one real, one exaggerated. the real vulnerability is their dependence on dollar funding, due to the scale of their international activities, which they may have been initially too slow to address effectively. it is currently being dealt with through a combination of deleveraging and consolidation. in the meantime, in order to ease this transition, the eurosystem, together with other central banks across the world, has decided to conduct us dollar liquidity - providing operations with a maturity of three months. a more exaggerated concern about french banks is their exposure to sovereign risk. let me just point out some facts : total exposure of major french banks to the sovereign risk of socalled “ peripheral countries ” amounts to 60€bn. to take an extreme – and from my view point – totally unrealistic scenario – a 50 % haircut on greece and 25 % haircut on italy and spain would result in a 12 % loss