This introduction presents an overview of key concepts discussed in subsequent chapters of this book. The book explains the rethinking of the social sciences and humanities prompted by the arrival of the 'Age of Humans', an ironic moniker since modernity has supposedly been the age of humanism. It draws together scholars who have a prescient insight into the significance of the new epoch. Some critique the idea of the Anthropocene from various social science perspectives, while others argue that the Anthropocene demands a re-examination of those very social sciences. Politics in the Anthropocene is about the collision of the system Earth with the system world, traditionally conceived as the political and social organisation of the former, which served as a background for the latter. The advent of the Anthropocene challenges some established boundaries between nature and culture, between climate and politics, between natural sciences and the social sciences and humanities.