D H Meadows, D L Meadows, J Randers and W W Behrens for The Club of Rome (1972)

In 1968 the Club of Rome, an international group of scientists, industrialists, economists and philosophers, initiated a remarkably ambitious enquiry into the predicament of humankind. With a membership of about seventy people from twenty-five countries, none of whom held public office, they were united by the conviction that the major problems facing humankind are of such complexity and are so interrelated that traditional institutions and policies are neither able to cope with them nor to comprehend them in their entirety.

They defined the intentions of the project as to examine the complex of problems troubling men of all nations: poverty in the midst of plenty; degradation of the environment; loss of faith in institutions; uncontrolled urban spread; insecurity of employment; alienation of youth; rejection of traditional values; and inflation and other monetary and economic disruptions. (p10)

From the start they recognised that these problems have three characteristics in common: they occur to some degree in all societies; they contain technical, social, economic, and political elements; and, most important of all, they interact. (p11) They felt that mankind's failure to understand and tackle effectively the problems was in large part due to examining each in isolation from the rest and not understanding that the whole complex of problems is larger than the sum of its parts. To try to remedy this they studied the interactions of five basic parameters of growth on a global scale - population, agricultural production, natural resources, industrial production, and pollution.

Their conclusions were stark:

[1] If the present growth trends in world population, industrialization, pollution, food production, and resource depletion continue unchanged, the limits to growth on this planet will be reached sometime within the next one hundred years. The most probable result will be a rather sudden and uncontrollable decline in both population and industrial capacity.

[2] It is possible to alter these growth trends and to establish a condition of ecological and economic stability that is sustainable far into the future. The state of global equilibrium could be designed so that the basic material needs of each person on earth are satisfied and each person has an equal opportunity to realize his individual human potential.

[3] If the world's people decide to strive for this second outcome rather than the first, the sooner they begin working to attain it, the greater will be their chances of success. (pp23-24)

The analysis of global futures was based on a computerised method of understanding the dynamics of complex systems called System Dynamics. This is how the model is structured: the level of global industrial output is determined by the input of industrial capital, by the input of non-renewable resources (minerals and fossil fuels) remaining in the world, and by the consumption rate - which depends upon the size of the world population and the per capita consumption rate. Changes in the population depend in part upon the proportion of the population in the age range 16 to 45, which depends upon the birth rate in an earlier period and on the death rate in that age group now. The death rate is influenced by: pollution, which depend upon levels of industrial output; levels of health service available, which depend in part upon the extent to which the income from industrial output is spent on health services; and levels of food supply, which depend in part upon the amount of arable land available and upon the level of food yield, which depends in part upon the investment in agriculture. Since the reserves of non-renewable resources and the amount of arable land are finite, there is inevitably a limit to population growth and to industrial growth.

What the computer plots based on this model showed was that, because parameters such as population and industrial production tend to change exponentially, when the reserves of resource and land run out, the effect on food per capita and industrial output per capita, is catastrophic. The ‘standard world model’ (which today would be called ‘business as usual’) assumes no major change in the physical, economic, or social relationships that have historically governed the development of the world system. It follows historical data from 1900 to 1970, and then plots the next 130 years to 2100 AD. The report describes the ensuing scenario in these words:

Food, industrial output, and population grow exponentially until the rapidly diminishing resource base forces a slowdown in industrial growth. Because of natural delays in the system, both population and pollution continue to increase for some time after the peak of industrialization. Population growth is finally halted by a rise in the death rate due to decreased food and medical services. (p124)

The report introduces a number of technological variants on the standard world model, such as doubling the resource reserves, increasing the control of pollution and increasing agricultural productivity: the time scale changes, but still the basic behaviour of the model is exponential growth of population and capital, followed by collapse. The authors identify their goal as a world system which is sustainable without sudden and uncontrollable collapse and which is capable of satisfying the basic requirements of all its people. They conclude that this can be achieved only if there are deliberate constraints on population growth and industrial growth, coupled with resource-conserving and non-polluting technologies.

They were able to formulate a stabilised world model (p168) if the following policies starting in 1975: (1) effective birth control being available to all and the average desired family size being two children; (2) average industrial output per capita remaining at the 1975 level and the industrial capital investment rate being set to match the depreciation rate; (3) capital being diverted from industrial investment to food production irrespective of whether it is judged an 'economic' investment; (4) soil enrichment and anti-erosion measures becoming a high priority; (5) resource consumption per unit of industrial output being reduced to one quarter of the 1970 rate; (6) the economic preferences of society shifting from material goods towards greater access to services; (7) pollution per unit of industrial and agricultural output beings reduced to one quarter of the 1970 rate; and (8) the lifetime of industrial capital being increased, entailing greater durability for machinery and emphasis on repair rather than discard.

The Executive Committee of the Club of Rome, in a commentary at the end of the book, drew this conclusion:

Our posture is one of very grave concern, but not of despair. The report describes an alternative to unchecked and disastrous growth and ... indicates that it may be within our reach to provide reasonably large populations with a good material life plus opportunities for limitless individual and social development … The concept of a society in a steady state of economic and ecological equilibrium ... is so distant from our experience as to require a Copernican revolution of the mind. Translating the idea into deed, though. is a task filled with overwhelming difficulties and complexities … only the conviction that there is no other avenue to survival can liberate the moral, intellectual, and creative forces required to initiate this unprecedented human undertaking. (pp195-196)