The terms ‘sustainable’, ‘sustainability’ and ‘sustainable development’ are commonly used in the literature of businesses, governments, local councils and many other organisations. What is usually being referred to is ‘mainstream sustainability’, an anthropocentric version of sustainability which involves only small-scale reform of the existing western development paradigm.
However, there are many alternative types of sustainability and sustainable development, some of which involve the radical restructuring of our economic, political and social structures.
In fact there is a whole spectrum of sustainability ranging from the most anthropocentric version, commonly called very weak sustainability, to the most ecocentric version, known as very strong sustainability. This categorisation of the types of sustainability was first proposed by Baker (2006) in his ‘ladder of sustainability’.
All versions of sustainability have one important point in common: they treat the consumption of natural resources as a cost and not as income when calculating GDP figures. Traditionally, economics count the use of the Earth’s resources as income. (Dresner 2002).
Very weak sustainability
Very weak sustainability is the lowest rung on Baker’s ladder and lies at the most anthropocentric end of the spectrum. Nature is valued only for what it can do for humans and the focus is on continued economic growth. The only environmental concerns are the scarcity of resources and the exhaustion of pollution sinks. Very weak sustainability is strongly ‘technocentric’ and takes the view that all natural capital can be substituted for human capital.
Again, weak sustainability is anthropocentric and technocentric but it does take environmental degradation more seriously than very weak sustainability. It involves a managerial approach to the conservation of resources and to environmental degradation in which the services and goods provided by nature are assigned an economic value.
Weak sustainability is associated with, and informs, mainstream sustainability and is what most organisations mean when they refer to sustainability: a greening of the current capitalist system of production and consumption.
Proponents of weak sustainability believe in a high degree of substitutability but also in the preservation of ‘critical natural capital’ – the natural capital that is needed for human survival and cannot be substituted for.
Strong sustainability is ecocentric and assigns intrinsic value to nature. It contends that overall levels of natural capital should not decline and that very little substitutability is possible.
Strong sustainability is a much more radical concept compared to the reformist nature of weak and very weak sustainability and promotes the creation of a ‘deep green economy’ in which the environment is viewed as an interconnected whole.
Very strong sustainability
Also known as the ‘ideal model’, very strong sustainability is the top rung of Baker’s ladder. It is an extremely preservationist approach in which the economy and therefore development is strongly regulated. Many proponents of very strong sustainability call for a reduction in the global human population and in the size of the global economy. Every species is held to be equally important to the human species.
Very strong sustainability is often criticised as being idealistic, impossible to achieve and anti-development in its outlook. It would undoubtedly be very difficult to operationalise and may well, at least in the short-term, discriminate against the existing poor by halting or slowing development in less-developed nations.
The value of arranging the different variations of sustainability into a spectrum is that it demonstrates how the most extreme ends are impossible to implement and indeed, probably undesirable, and that the type of sustainability we need to adopt will most likely be an approach that draws on points from all four types.