 I think this is a huge challenge for all of us and I want to congratulate you, especially the younger people here in the room. You are the first generation which will have to deal with the challenge to guarantee the survival of the human species. And let me say this, we underestimated all together, I include myself, we underestimated this challenge. We thought there is plenty of time, there isn't. So you know ultimately climate change is now the priority but therefore if you're making that the priority there's going to have to be some trade-offs, economic, social, political. How do we manage to find the right trade-off? I think such a big change, it's easy said we have to decarbonize but what does that mean? This means to create a complete new energy system, even more to create a complete new industrial society. We need a spirit of cooperation which isn't there. At the moment there is rivalry of the great powers. I'm still an optimist. It's a very complicated political game to balance this trade-off. The divergence that you see in the states at the moment, again, how would you address it? How would you try and solve it? We have this discussion in Switzerland. One of the wealthiest nations in the world and Switzerland is part of Europe and Europe is still one of the wealthiest continents in the world. We have to understand that it's not only a challenge for science or we have a distribution problem, we have to help the global south to join this effort because once the climate is out of control, border doesn't matter. The climate is a global challenge. Who do you think ultimately should be paying for the damage that we're doing to the environment? Should there be some sort of carbon tax? I think the global carbon tax will be extremely complicated to push that through because the US will say no and some other important players will do the same. But I think in Europe it would be a huge achievement, a huge opportunity if we could decide about implementing a carbon tax. At the moment it's complicated, but I think it can be done. When you increase the carbon tax, you have to reduce the taxes on a different side. It must be done because it's also in our economic interest. But I think the biggest risk is if we don't act, if we don't act forcefully now.