The days of the world as we know it are numbered. Like the passengers of the Titanic, we run into the dark night dancing and laughing, with the selfishness and arrogance of superior beings convinced of being "masters of themselves as of the universe". And yet, the warning signs of sinking accumulate: climate disruptions in series, omnipresent pollution, exponential extinction of animal and plant species, anarchic plundering of resources, multiplication of health crises. We behave as if we are alone in the world and the last generation of men to occupy this Earth: after us, the Flood ... Nicolas Hulot has traveled our planet in all latitudes. No one knows it better than him: it is a cramped space with precarious equilibrium. This book is a final cry of warning before giving way to despair: if all of us, rich and poor, do not immediately change our behavior to "do better with less" and put ecology at the center of our individual and collective decisions, we will sink together. We must be in solidarity with life and the future: this warning, Nicolas Hulot has become the passionate and indefatigable messenger, from the Johannesburg summit to the school of his village, the golden paneling of the Elysee to the farms of Brittany and Lorraine. I am not a born ecologist, he tells me, I have become one. And we too can, we must become. Titanic Syndrome is an essential book, to read urgently. With Nicolas Hulot, we will not be able to say that we did not know.