The Limits to Growth

Abstract established by Eduard Pestel. A Report to The Club of Rome (1972),

by Donella H. Meadows, Dennis l. Meadows, Jorgen Randers, William W. Behrens III

Short Version of the Limits to Growth

Our world model was built specifically to investigate five major trends of global concern – accelerating industrialization, rapid population growth, widespread malnutrition, depletion of nonrenewable resources, and a deteriorating environment.

The model we have constructed is, like every model, imperfect, oversimplified, and unfinished.

In spite of the preliminary state of our work, we believe it is important to publish the model and our findings now. (…) We feel that the model described here is already sufficiently developed to be of some use to decision-makers. Furthermore, the basic behavior modes we have already observed in this model appear to be so fundamental and general that we do not expect our broad conclusions to be substantially altered by further revisions.

Our conclusions are :

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.

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.

All five elements basic to the study reported here–population, food production, and consumption of

nonrenewable natural resources–are increasing. The amount of their increase each year follows a pattern

that mathematicians call exponential growth.

A quantity exhibits exponential growth when it increases by a constant percentage of the whole in a

constant time period.

Such exponential growth is a common process in biological, financial, and many other systems of the

world.

Exponential growth is a dynamic phenomenon, which means that it involves elements that change over time.

(…) When many different quantities are growing simultaneously in a system, however, and when all the

quantities are interrelated in a complicated way, analysis of the causes of growth and of the future behavior

of the system becomes very difficult indeed.

Over the course of the last 30 years there has evolved at the Massachusetts Institute of Technology a new

method for understanding the dynamic behavior of complex systems. The method is called System

Dynamics. The basis of the method is the recongnition that the structure of any system–the many circular,

interlocking, sometimes time-delayed relationships among its components–is often just as important in

determining its behavior as the individual components themselves. The world model described in this book is

a System Dynamics model

Extrapolation of present trends is a time-honored way of looking into the future, especially the very near

future, and especially if the quantity being considered is not much influenced by other trends that are

occuring elsewhere in the system. Of course, none of the five factors we are examining here is independent.

Each interacts constantly with all the others. We have already mentioned some of these interactions.