This document summarizes Hervé Kempf's presentation on the link between ecological and social crises. [1] The growing inequality between the very rich oligarchy and the rest of society is exacerbating environmental damage because the oligarchy sets a culture of excessive consumption. [2] Reducing consumption by the wealthy elite would help address both social injustice and environmental degradation by lowering overall resource use and inspiring less wasteful social norms. [3] Tackling inequality is thus key to averting deeper ecological and economic crises.