The end of the world – that’s what heading into the twenty-first century looks like with on the one hand, increasing inequalities, states powerless against economic globalization, and an upsurge in forms of nationalism; and on the other hand, man-induced climate change and the depletion of non-reproducible natural resources. But just what is a world and which world is it that is coming to an end? This is the question this essay on social and human sciences sets out to answer. Various worlds have come and gone throughout history. The one that is ending right now is not ‘the modern world’ but merely a “first modernity” world. It rests on the pairing of a particular cosmology and an equally particular ideal of justice. That cosmology is dualistic, separating humankind from Nature which is looked upon as resources to be drawn on at will. The ideal of justice, consists in a mode of justification of the ‘right’ social norms for each nation, retaining those that are favorable to economic growth and in distributing the output of this growth to the population. Although the world is currently in crisis, it is not the end of history. This book sets out two blueprints – one reformist, one revolutionary – for what can be termed second modernity. The reformist blueprint, to which the author’s preference goes, saves a place for each Nation. It imparts a new direction to European construction that might shift its current geographical borders. This ground plan for re-founding social democracy is meant as an alternative to the dead-ends of left-wing neoliberalism, which vindicates economic globalization without political globalization. The future materialization of that plan is dependent neither on chance nor on necessity but on a collective action that must be both bottom-up and top-down. The hope is that this book will contribute to that action by forging a vision that can fill the void that has arisen with the failure of revolutionary socialism and the exhaustion of reformist socialism.