Not many people know the details of World Dynamics. So it is
important to have at least some of the details to promote intelligent
discussion. Here are some key quotes from Jay Forresters
World Dynamics (Wright-Allen Press, Cambridge, 1971):
1) His comment on criticism of the World Dynamics model:
"It is hoped that those who believe they already have some different
model that is more valid will present it in the same explicit detail,
so that its assumptions and consequences can be examined and
compared. To reject this model because of its shortcomings without
offering concrete and tangible alternatives would be equivalent to
asking that time be stopped. But the world will continue to turn.
We always use the most acceptable model at any point in time.
But how should we proceed so that the most acceptable model is
also the best one that is available? We should try for three things.
First, the best existing model should be identified at each point in time.
Second, the best currently existing model should be used in preference
to traditional models that may be less clear and less correct. Third,
aggressive effort should be devoted to a continual improvement in the
available models of the world system." p. ix
2) On the counterintuitive nature of the high leverage policies for
controlling complex systems:
"From this book the reader should glimpse the nature of multi-loop
nonlinear feedback systems, a class to which all our social systems
belong. The book has shown how these systems can mislead us because
our intuition and judgment have been formed to expect behavior
different from that actually possessed by such systems.
"The theory of world structure as described in Chapters 2
and 3 may seem oversimplified. On the other hand, the model presented
here is probably more complete and explicit than the mental models
now being used as a basis for world and national planning. The human
mind is not adapted to interpreting the behavior of social systems.
Over the long history of evolution it has not been necessary for man
to understand these systems until very recent historical times.
Evolutionary processes have not given us the mental skill needed
to properly interpret the dynamic behavior of the systems of which
we have now become a part.
"This concern about the deficiences in our mental models is not
a matter to be taken lightly. The world is still pursuing programs and
policies that will be at least as frustrating as those in the past. If we
follow intuition, the trends of the past will continue into deepening
difficulty." p. 123
3) The high leverage policies, found in World Dynamics(1971),
that will bring the world into equilibrium:
a)Summary:
"Natural-resource-usage rate reduced 75%
Pollution generation reduced 50%
Capital-investment generation reduced 40%
Food production reduced 20%
Birth rate reduced 30%" p. 120
b)A few other key insights from the model:
1) "Reduction of investment rate and reduction in
agricultural productivity are counterintuitive and not likely to be
accepted without extensive system studies and years of argument -
perhaps more years than are available." p. 121
2) " Again it must be stressed that only pressures and
influences will bring exponentially growing population and capital
investment into balance with a fixed or even declining environmental
capacity. The pressures can be tangible like the ones represented in
Figures 6-5 and 6-6. In these figures the pressures come from
lowering the emphasis on capital accumulation (including medical
and health expenditures for facilities and education) and reversing
the present ever-increasing emphasis on food production." p. 118
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Item#3 above, particularly item 3b, indicates why World Dynamics
is so controversial.
Arlen Wolpert
Independent Scholar
411 Franklin Street, Apt. 1008
Cambridge, MA 02139 USA
Telephone: (617)547-6994
email: awolpert@world.std.com