Beginning in the 1990s, the 'posthuman' has evolved as a chameleon-like concept designating everything from the transhumanist project to assure the continuity of humanity beyond the limits of human embodiment to the critical interrogations of suspect ontological boundaries separating the human from the non-human world writ large. Our discussion will be framed around two contemporary challenges to the human: how climate change repositions the human within larger, cosmological process; and how AI seeks to subsume the human into a generic model of intelligence.