That the over-shoot of planetary ecosystem boundaries is a limit to capitalism — and to human population growth and consumption — like no limit we have faced before, is what the global movement of school-strikers is trying to tell us. It is what the Extinction Rebellion movement is telling us.
What does this mean for political economy? Well, if I can repeat an argument I made in the pages of SPE in 1994 (25 years ago!) we have to stop thinking, programmatically, in terms of economic growth. We must take up the calls for degrowth — in whatever discursive form best fits our political contexts — and for the rapid decarbonization of our systems of production, consumption, communication, and transportation.