These notes are from the “The logic of sufficiency”  as described in .
The idea of sufficiency begins to shift to the principle of sufficiency when structure is needed for enactment, when more than sensory perception of “enoughness” or “too muchness” is needed to recognise excess and to act. Unlike the normatively neutral concepts of efficiency and cooperation, Thomas Princen contends that sufficiency as a principle aimed at ecological overshoot compels decision makers to ask when too much resource use or too little regeneration risks important values such as ecological integrity and social cohesion: “when material gains now preclude material gains in the future; when consumer gratification or investor reward threatens economic security; when benefits internalized depend on costs externalized”. Princen sets out an argument for the installation of social organizing principles attentive to risks, especially those risks that are displaced in time and place, are desperately needed in the belief that sufficiency principles (as opposed to mere efficiency) such as restraint, respite, precaution, polluter pays, zero, and reverse onus, have the virtue of partially resurrecting well-established notions like moderation and thrift, ideas that have never completely disappeared.
Princon’s mentions a few real world examples where the logic of sufficiency has already been embraced by companies or communities as the basis of doing well. With examples ranging from timbering and fishing to automobility and meat production, Princen shows that sufficiency is perfectly sensible and yet absolutely contrary or modern society’s dominant principle, efficiency. He argues that seeking enough when more is possible is both intuitive and rational –personally, organizationally, and ecologically rational. And under global ecological constraints, it is ethical. Over the long term, an economy –indeed a society– cannot operate as if there’s never enough and never too much.
 J. Barry and P. Doran, “Refining green political economy: from ecological modernisation to economic security and sufficiency,” Analyse und Kritik-Zeitschrift fur Sozialwissenschaften, vol. 28, no. 2, p. 250, 2006.
 T. Princen, The logic of sufficiency. MIT Press, 2005.