The currently dominant economic paradigm contains a future vision of increasing material well-being, reliance on technological fixes to environmental degradation, and reduction of poverty and other social problems by continuous economic growth.  Considerations of sustainable ecological scale (see Understanding Scale; Areas of Concern; Causes of Scale Problems) indicate that this vision of the future is inconsistent with fundamental laws of science, ethical concerns for just distribution, and the evidence of what constitutes human happiness and well-being (see Understanding Human Happiness and Well Being).  Yet the notion of continuous economic expansion of the market economy as the solution to humanity’s major challenges persists.

 

If the current paradigm is not sustainable, then what is an alternative vision for humanity’s future?  There are many possible visions of a sustainable future, which might differ in terms of the emphasis on technology, the level of material consumption, the size of the global population, the role of trade, the system of decision making, and in many other ways. Indeed, if people are to live in harmony with their immediate environment, different solutions will likely emerge based on the different biophysical characteristics of local and regional areas. Social and cultural diversity will both influence visions for, and be reinforced by, a sustainable planet.

 

Various groups have begun exploring these possibilities, but it is not our purpose here to choose among them, or to describe in detail what the most desirable vision might be. Such a process will inevitably be a slow evolution, integrating insights and aspirations from many people, and vary from region to region. Our purpose is threefold:

Quantitative growth involves an increase in size. Qualitative development involves an improvement in functioning. Over the last 250 years both quantitative growth and qualitative development occurred in some human societies as the result of economic growth.  Greater comforts and well-being came in part from more productive farming, industrial production and trade. Quantitative development was so successful that it allowed global population to increase more than 500% in less than 200 years, and for this ever expanding human civilization to impact every area of the planet. 

One of the greatest benefits of this growth in the human economy is the surpluses it provides for some, beyond the basic needs of food and shelter.  These surpluses support innumerable qualitative developments –through improvements in the quality of life by removing the drudgery of earlier societies, increasing human health status and life span, and encouraging science and the arts to flourish - at least for some.  The major benefits of economic growth have been in these qualitative improvements, not just in the increasing size of the economy itself. 

The surpluses from quantitative growth generate levels of material consumption beyond those required for human happiness and well-being.  These surpluses, enjoyed by only a small portion of the world’s population, are also generated in extremely wasteful ways, which unnecessarily degrade ecosystems. The maldistribution of material goods creates problems of excess for some, and poverty for others. The relationship between growth and development is not a simple, linear one, as the current economic paradigm implies.

Distinguishing between quantitative growth and qualitative development helps identify important differences:

With this distinction, the broad goals for a sustainable future become clearer: reduce quantitative growth of material throughput to remain within ecologically sustainable scale, and increase the qualitative developments which contribute to human happiness and well-being.   

One of the biggest challenges in making a shift to a sustainable future is in refocusing our policies and practices across a variety of fields, from economic growth to qualitative development.  The focus on economic growth was appropriate for an earlier phase in human history when material goods were scarce, and more such goods contributed to human well-being. This is still true for meeting the needs of the world’s poor.

 

Continuing an exclusive focus on economic growth, especially in affluent countries, is counterproductive to a sustainable future. Balancing economic growth where it is needed (giving priority to meeting the needs of the poor, and in affluent countries focusing on maintaining basic infrastructure), with a focus on qualitative improvements for all, is a more certain route to sustainability.

The last century and a half has been anomalous regarding the enormous growth in energy supply made possible by the use of fossil fuels (see Energy). While fossil fuels will be available for several decades to come, they will soon become increasingly expensive, difficult to extract, and polluting.  The required transition to renewable energy sources will be the first time in human history that an adjustment from one fuel source to another involves a decrease in energy intensity – the amount of work available from a quantity of fuel.

 

Renewable energy sources have lower energy returns on energy invested than fossil fuels (see Energy).  The implications of this physical reality are that either we prepare ourselves to invest considerably more financial resources to maintain the energy supply we currently experience, or we prepare ourselves to manage with considerably lower levels of total energy. It is highly unlikely that global energy supplies can continue to grow into the next century, as is currently assumed, without disastrous ecological impacts. Learning to live comfortably with less energy will become a necessity.

From a global perspective, optimal scale determines a sustainable level of throughput, considering acceptable risks, for a given population. The greater the global population, the lower the average per capita level of throughput at that risk level. If there is a fixed amount to go around, then it will have to be spread more thinly the more people there are to share with.  Higher populations will thus push decisions about optimal scale either to lower levels of average per capita consumption, or to accept higher risks of exceeding sustainable scale if consumption levels are too high. The sensitive issue of global population policy will need to be part of the discussion regarding optimal scale (Population).

The Ecological Footprint Measure (see Ecological Footprint) indicates that global throughput levels have been exceeding the annual income produced from natural capital for several decades.  When viewed against the bioproductive land available globally (now about 1.8 hectares per capita), the Ecological Footprint for 2001 was 21% over this limit.  These data indicate that global throughput currently exceeds sustainable scale as well as optimal scale by a considerable margin. Countries near the 1.8 ha/capita available, Jordan, Rwanda, Ecuador and Gabon, may or may not be considered as desirable societies to emulate. 

Any decisions to reduce global population to achieve a higher level of per capita throughput would take decades to have an effect. Since the bioproductive land available is fixed (or actually declining as would be expected from the excessive drawn-down of natural capital reflected in ecological overshoot data), and the global population is going to rise by at least 2 – 3 billion over the next few decades, it appears the only way to reduce this ecological overshoot and approach ecological sustainability is to reduce our absolute level of throughput for the foreseeable future.  While optimal scale is the ultimate goal for overall sustainability, the more immediate need is to move to an ecologically sustainable level of throughput.

Population size is a sensitive cultural and moral issue for many people and nations.  It is also difficult to predict with any accuracy more than a few years ahead. (choen) Whatever the size of future populations, it will have a dramatic impact on ecological sustainability and human well-being, and therefore deserves considerably more attention than it is currently getting.  Any planning for a transition to sustainable scale must consider the impact of population on global throughput, the tradeoffs between sustainable levels of throughput and population size, and the considerable uncertainties associated with long term population projections.

There is little doubt that human activities are altering global ecosystems, and that this is happening more rapidly than previously understood (see Ecosystem Functions & Services; Areas of Concern; Millenium Ecosystem Assessment). These changes are unanticipated consequences of economic growth, population increases and technological designs. Ecosystem science is in early stages of development.

 

We do, however, know enough to realize that these global systems changes will have significant negative impacts on human well-being, although details regarding magnitude and timing remain uncertain.  We know that multiple global systems are affected, that these systems are interdependent, and often respond in non-linear ways to the kinds of stresses now occurring, creating unwelcomed surprises. We have unintentionally created a high risk, highly uncertain situation, with potentially disastrous and irrevocable consequences.

Such challenges call for a cautious approach. International environmental treaties and many national and local policies have incorporated the Precautionary Principle as a way of dealing with these challenges (Science and Environmental Health Network, 2004; Rachel’s Environment and Health News, 2002).  The Precautionary Principle states that [ quote ].  It recognizes our lack of knowledge regarding ecosystem dynamics, while appreciating our dependence on the enormous benefits they confer.  It also recognizes the potentially irreversible and extremely high risks involved in altering these systems as an unintended by-product of economic growth. Adopting a precautionary approach is an essential component of implementing a scale perspective.

Major threats to ecological sustainability are usually taken seriously only after costly disasters occur.  Environmental problem solving has been end-of-pipe, and symptom-focused, rather than proactive, preventive, and design focused.  Now that the unintended negative consequences of our approach to economic growth are becoming clearer (see Areas of Concern), and the bases of our economic paradigms coming into question (see Causes of Scale Problems), waiting for disasters is neither necessary nor desirable.

 

It is now possible to focus on prevention of scale problems as new economic and development activities are planned and implemented (see Supportive Public Policies; Economics For Community; Sustainable Business Practices; Institutions for a Sustainable Future; and Lifestyle Solutions). Focusing on prevention across a broad range of human activities is essential to implementing a sustainable scale perspective.