Strong vs Weak sustainability

Strong vs Weak Sustainability: two different approaches to Sustainable development. The former defines development as non-consumption of natural capital the latter defines development as non-consumption of overall total capital (including human and social capital).

In the late 70s as the environmental issue started to unfold and to be addressed by economists, different theories questioning the resource paradigms. starting from the same question on how can we make the generations yet to come have the same opportunities of satisfying their needs as we have been able to do. Two theories emerged over the others, Strong and Weak Sustainability. In a nutshell, according to Strong Sustainability the consumption and regeneration of natural resources (natural capital) due to a generation should balance each other out, whereas according to Weak Sustainability, the balance should be in overall resources, including human and social capital.

Indeed, according to Weak Sustainability variations of different types of capital such as natural capital or manufactured capital can be accepted as long as the aggregate total capital remains constant or increase. On the other hand, Strong Sustainability advocates stress the fact that consumption of natural capital is usually not reversible, while manufactured capital can be restored with new goods. One more feature that is highlighted by Strong Sustainability is that manufacturing capital can not be perfectly exchanged with natural capital as natural capital is required for any kind of production and provides security, basic materials for a good life, health, and good social relations. Eventually, the whole Strong Sustainability point, comes down to find the “critical natural capital” that is the threshold of defining how far can we go in consuming resources without irremediably affecting the well-being of the generations yet to come.

Basically, one example of a Weak Sustainability approach is the concept of carbon tax. If you do not know what I am writing about, check in our dictionary! Back to the carbon tax, as we do think that a certain amount of pollution is not undermining human well-being as long as it can be compensated, the degradation in natural capital due to CO2 emissions can be offset by an increase in public capital


From an operative point of view Weak Sustainability is much more implementable in the short run than Strong Sustainability. In fact, one of the main issues with Strong Sustainability is defining the tolerance threshold: this is due to multiple factors. First, before even debating the norm there is the need to a scientific assessment of the well-being that natural capital provides to the public, but this is very difficult due to the fact that the “natural service” provided is a “multidimensional” service, of whom not only humans benefit. Second, the definition of such a threshold involves cultural values that may differ from nation to nation, thus leading to different norms.