Аннотация:Abstract Capitalism cannot exist without continuously expanding production of an 'immense collection of commodities' around the world. However, there is an irrefutable fact that is jeopardizing capitalism and its chimerical claims of sustained economic growth: the planet has biophysical limits. Twenty-first-century socialism, therefore, cannot rely on the dynamics of economic growth. It rather has to build a world economy that not only frees workers from exploitation, but releases nature from irrational exploitation as well. In fact, for socialist countries to withdraw from growth represents the paramount environmental challenge to be overcome. This means moving from ostentatious consumption towards a new principle of moderation. This is the essential foundation for an economy that operates within the limits of our biophysically finite world. Keywords: sustained growthconsumptionsocialismprinciple