The field of economics ought to be based on the fact that planet Earth is a rare Earth that is fundamentally an Ocean and Plant World. The rapid and continuing bulldozing of biodiversity across ocean and land that has been a feature of human society’s economic development over the past two centuries or so, demonstrates that the current political and economic response, framed by the narrow human-centric concept of sustainable development, has failed. Therefore, this paper calls for a fundamental planetary turn in perspective, moving beyond sustainability towards the biocentric concept of Planetary Habitability. The point is that fixing a slow leak in a spaceship (sustainability) is insufficient when the ship’s entire life support system is collapsing due to a fundamental design flaw (anthropocentrism); instead, the focus must shift to ensuring the entire ship can support life (habitability), regardless of immediate human convenience.