Sander E. van der Leeuw
Climate and Society: Lessons from the Past
10 000 Years
This paper distinguishes three major ‘‘revolutions’’ in the
socio-environmental interactions that reflect growth in the
extent to which human beings invest in and modify their
environments. As people settled in villages during the
Neolithic, interactions between more people became an
important element in survival strategies, shifting the
emphasis in survival strategies from mobility to sociality.
The emergence of cities changed human societies by: i)
creating dependencies between more and more distant
regions, ii) increasing the degree of aggregation of
human populations, iii) narrowing the range of subsistence
resources on which people depended, and iv)
increasing further their investment in the natural environment
and in material culture. Altogether, urbanization
drove human social systems further and further away
from flexibility and rapid adaptation to environmental
change, while increasing the demands on the social
system, including major increases in energy and matter to
support urban populations. This was achieved by linking
together larger and larger hinterlands for these cities, in
effect creating Empires. The fundamental change is one
from humans responding to environmental change and
disruption by migration to humans investing in the
environment, and therefore responding to environmental
change by problem solving. One therefore needs to look
at the combined socio-environmental systems over the
longer term that reflect the buildup and culmination of the
shifts in the social and environmental risk spectra due to
the human-environmental interactions in periods before
the ‘‘crisis’’ occurs, which are a fact of life in any society’s
interaction with its environment, and should be seen as
"social" challenges rather than ‘‘environmental’’ ones.
These are generally due to the fact that the society in
question has invested so much in a particular way of life
that it cannot innovate itself out of difficulty before time
runs out. This implies that we have to shift our thinking
about socio-environmental issues, from ‘‘population
thinking’’ to ‘‘organization thinking.’’ In this perspective,
a crisis does not imply the disappearance of the people
involved, but a transformation of the organization that
links them.
STUDYING THE LONG TERM OF GLOBAL CHANGE
The disciplinary divisions in the western intellectual tradition
have, until recently, maintained a disconnect in the study of
global change between the geological and life sciences on one
hand and the social sciences and humanities on the other.
Whereas the former studied the evolution of our natural habitat
over the very long term (millions of years), the latter focused on
the evolution of human societies over a much shorter period
(3000 or 4000 years). And while the former implemented an
actualist perspective (similar causes have similar effects,
irrespective of the moment at which they occur) and reconstructed
the past on the basis of processes investigated in the
present, the latter perceived the present as the result of processes
operating in the past. The two groups of disciplines thus
Photo: S. E. van der Leeuw.
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encountered each other in the present and recent past, for which
experimental data were available on the natural environment
and written data on the history of human societies.
This disconnect is quickly changing. On one hand, this is the
result of the rapid development of the archaeological sciences
(see next section), which has transformed archaeology from a
historical into a scientific discipline in the last 30 years, while
hugely increasing our knowledge about both the social and the
environmental aspects of the more distant past. On the other
hand, the spread of the complex adaptive systems approach in
the life sciences has made these disciplines more ‘‘historical’’ in
the sense that it is nowadays acknowledged that one cannot
simply deduce a system’s past trajectory from its current state.
For the first time, we therefore have an intellectual
perspective that allows us to truly investigate the interaction
between societies and their environments (rather than investigating
each of them separately and then hypothesizing about
their interactions) and to do so over the very long term. This
perspective is of great importance to the study of global change.
First, we can now confidently include the role of millennial and
even longer processes in our attempts to understand what is
happening in the present. Evidently, such dynamics have always
played a role in processes such as tectonics, erosion, and species
evolution as well as cultural change. Second, this new
perspective allows us to study complete cycles of human–
environment interaction, from the beginning until the very end,
rather than studying only the last few hundred years of
interaction, by which time the environment has already been
heavily impacted by the society concerned. And third, we can
now take the change of change into account, such as the change
from long-term investment in the environment to ‘‘dealing with’’
the environment over the short term. Together, these three
advances in the approach to global change investigation also
allow us, importantly, to identify long-term shifts in socioenvironmental
risk spectra (‘‘environmental time-bombs’’).
ARCHAEOLOGY AND GLOBAL CHANGE STUDIES
In barely 40 years, archaeology has undergone a complete
transformation. From a historical discipline based in the study
of Classical and Mesopotamian antiquities, it has increasingly
become an interdisciplinary field of study that draws heavily on
history, anthropology, technology, and a wide range of natural,
life, and geological sciences in its study of past life-ways (rather
than monuments and objects). This has led to the blossoming of
a number of subdisciplines, such as archaeo-zoology, palaeobotany,
archaeo-geography, and palaeo-pathology, and the
adaptation of a wide range of sophisticated techniques from the
natural and life sciences to archaeological studies; these
techniques include genetic analysis, geophysical survey, remote
sensing, isotope dating and analysis, electron microscopy, and
so on. As a result, the archaeological record currently is the only
record of the past in existence that integrates such a wide range
of sources concerning the environment and human societies and
is independent of the biases of past authors.
These paradigmatic and technological changes have the
potential to place archaeology at the center of modern studies of
long-term global change. We are now able to complement
(polar and other) climate data with information on the
evolution of the terrestrial environment over many millennia,
including the evolution of flora and fauna, almost anywhere on
earth. Moreover, we can now draw on an important body of
information concerning the evolution of human behavior over
time. These two capabilities together allow us to study the longterm
interaction between humans and their environment at the
interface of environmental and social dynamics. And finally, we
can begin to downscale our understanding from the global to
the regional and even local scale. No longer do we therefore
study global environmental change; rather, we are able to study
regional socio-environmental change. This enables us to move
our efforts from, for example, the study of the mitigation of
global warming to the study of the ways in which humans have
adapted different lifestyles and environments to such changes.
But the downside of these changes currently is that
archaeology is a ‘‘slow’’ discipline. The meticulous gathering
of data, artifacts, and samples from the soil; the analyses
necessary to reveal the information that they carry; and the need
to excavate multiple sites before one may synthesize information
about the archaeology of a particular region are all very
time-consuming. In this way, the discipline as a whole moves
rather slowly. In addition, most of archaeology is nowadays
funded to prevent the loss of primary data; thus, an
extraordinarily large proportion of the practitioners of the
discipline are focused on gathering primary data rather than
analysis, synthesis, and publication. As a result, a large
proportion of the available data are never studied, let alone
brought to bear on the kinds of issues we are discussing here.
TEMPORALITIES, CONTINGENCIES, AND
CAUSALITIES
Natural and social processes simultaneously operate on a
multitude of timescales, from the millennium to the minute.
Traditionally, our thinking accommodates only a very limited
number of these timescales at any one time. Hence, most
research focuses on three or four timescales at most, leaving an
almost infinite number of them uncognized. Hence, it is very
difficult to determine ‘‘what did it’’ and the respective roles of
the social and the natural dynamics in the combined process.
Moreover, the spatial and temporal scales at which the different
disciplines operate are very different. Climate studies operate
spatially at the global scale and temporally at the decennial
scale or longer. Archaeology operates at the local spatial scale
and has a hard time reducing its temporal resolution beyond the
century. Social sciences operate at the local or regional scale and
temporally have resolutions down to the year or the season.
Hence, it is very difficult to create true intellectual fusion among
these (and other) disciplines.
The fact that we are dealing with extraordinarily complex
processes involving the atmosphere, the geosphere, the hydrosphere,
the biosphere, and the anthroposphere means that the
data are often open to multiple interpretations and that it is
difficult to decide between the different scenarios. This becomes
crystal clear when one realizes that the history of the Earth’s
climate itself is the result of the superposition of different cycles,
the evidence for which comes from different disciplines. Thus,
changes in the Earth’s axis combine with changes in our planet’s
distance from the sun and other astronomically observable
phenomena into so-called ‘‘Milankovitch cycles’’ of 100 000,
43 000, 24 000, and 19 000 years each (1). Cycles observed in
North American iceberg frequency (so-called ‘‘Heinrich events’’
[2]) have a periodicity of 7000 years. The proportion of 18O
isotopes found in Arctic and Antarctic ice cores, glaciers, and so
forth by Dansgaard and Oeschger cycles with a frequency of
7000 years, whereas in foraminifera, shorter cycles in the
oscillation of this oxygen isotope were found to occur every
1800 years by Bond (3). The latter have to do with acceleration
and deceleration in thermohaline circulation in the oceans.
Our attempts to see these complex matters clearly and to
identify the impact of these different cycles—and the human
responses to them—are further hampered by the fact that, while
it is relatively easy in archaeology to demonstrate contingency,
it is much more difficult to prove causality. Hence, archaeologists
often judge between scenarios on the basis of their
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internal consistency, rather than by ‘‘proving’’ or ‘‘falsifying’’
hypotheses against independent data.
All of these factors mean that, while we have many new data
and techniques at our disposal, we are, for the moment, far
from a consensus on how to use these data in the study of global
change.
WHAT ENSURED HUMAN SURVIVAL IN THE
PLEISTOCENE?
Throughout the Pleistocene, human beings survived many
major changes in the environment, such as the ice ages with
their extremely cold temperatures. Although humans achieved
major advances in cognitive and technical capabilities during
that period, they did not possess any advanced technical means
to defend themselves against the climate or the megafauna
(aurochs, woolly rinoceros, and feline predators). Moreover,
these human ancestors did not possess any advanced technical
means to defend themselves against the cold or the megafauna.
Moreover, they lived in very small groups, which were very
vulnerable to accidental extermination as only a few members
had to succumb to an accident for the group to become too
small to survive.
How was human survival possible? To understand human
survival, we need to take into account that human subsistence
strategies did not involve any investment in the environment to
raise any particular crop. Instead, they had a multiresource
strategy, harvesting from the environment what was on offer at
any one time, whether plant or animal foods. Humans’ high
mobility allowed them to move on as soon as resources became
scarce; very quickly they would have developed such knowledge
of their environment that they could anticipate some of the
recurrent, seasonal resource shortages and would know exactly
where to go to find another resource. In doing so, they would be
able to avoid any overexploitation of the landscape, staying well
below its carrying capacity. Their investment in the landscape
consisted of the knowledge they acquired about it.
From the perspective of environmental dynamics, humans
lacked the knowledge to truly interact with them. They did not
intervene fundamentally in nature’s processes and dynamics,
except for culling the products of it. Due to humans’ low
population levels, such culling was insufficiently heavy to have
any long-term effects on the landscape, the vegetation, or the
fauna. Hence, the natural processes essentially escaped their
control and were not modified by them.
Finally, from the perspective of risk, change and uncertainty
were the order of the day. Yet one sees in the archaeological
record that people attempted to minimize change and uncertainty;
they did this, for example, by living in (relatively)
enclosed and protected environments, such as caves, but also by
seeking out those environments for resource procurement that
were controlled by natural dynamics that limited the range of
variability. In Epirus, for example, toward the end of the
Palaeolithic, people focused on those environments in which
tectonic activity regularly reset the clock of vegetation change to
zero (4).
THREE MAJOR REVOLUTIONS IN 10 000 YEARS
The Holocene was the theater of three major transformations in
human social organization and its environmental corollaries,
which occurred relatively rapidly when viewed on an archaeological
time-scale (within a few thousand years of one another):
i) domestication of certain animal and plant species, leading to
the first long-term sedentary societies; ii) aggregation of human
populations in towns and cities; and iii) the development of
very large territorial empires.
In my opinion, the trigger for this acceleration is the fact
that, during the Palaeolithic, human beings crossed a threshold
in the development of their working memory (2). This enabled
the development of the conceptual apparatus necessary to
conceive of space in nested dimensions—0, 1, 2, 3—across a
wide range of spatial scales (from the individual fiber or grain to
the landscape), to separate a surface from the volume it
encloses, to use different topologies, to distinguish and relate
time and space, to distinguish between different sequences of
cause and effect, to plan, and so forth. As a result, innovation
was no longer an additive process; instead, it became an
exponential process when combinatorial possibilities of existing
concepts became the basis for generating new concepts.
It was as if, suddenly, human beings had achieved an
exponential increase in the dimensionality of the conceptual
hyperspace (‘‘possibility space’’) that governed their relationship
with the external world. This afforded them a quantum leap in the
Part of one of the glaciers at
Akulliit (Twin Glaciers). Photo:
His Majesty King Carl XVI Gustaf
of Sweden.
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number of degrees of freedom of choice they had in dealing with
their material and ideational environment and enabled them to
rapidly develop new cognitive tools and to intervene in their
environment, thus externalizing their mental capacities.
What Happened in the Neolithic?
From the end of the Palaeolithic, around 12 000 years ago, we
thus observe a drastic acceleration in the speed of invention and
innovation. Many new categories of artifacts emerge, new
materials are used, new techniques are introduced, and new ways
to deal with aspects of the material world are ‘‘discovered’’ in the
comparatively short time span of a few thousand years. The
acceleration is so overwhelming that in a few thousand years the
whole way of life of many humans on earth changes: rather than
living in small groups that roam around the Earth, people
concentrate their activities in smaller territories, they invent
different subsistence strategies, and in some cases they literally
settle down in small villages (3, 4).
Together, these advances greatly increased the number of
methods at people’s disposal to tackle the challenges posed by
their environment, allowing them to meet more and more
complex challenges in shorter and shorter timeframes. Hence,
these changes triggered a rapid increase in our species’
capability to invent and innovate in many different domains,
substantively increasing humans’ adaptive capacity. But on the
other side of the coin, these solutions, by engaging people in the
manipulation of a material world that they now partly
controlled, ultimately led to new, often unexpected, challenges
that required the mobilization of great effort to be overcome in
due time.
As part of this process, a number of fundamental changes
occurred. First, the relationship between societies and their
environments became reciprocal: not only did climate and the
environment impact society; from this point forward, society
impacted climate and the terrestrial environment. As a result,
sedentary societies tried to control environmental risk by
intervening in the environment, notably by i) simplifying or
even homogenizing (parts of) their environments, ii) narrowing
and optimizing the range of their dependencies on the
environment, and iii) engaging in spatial and technical
diversification and specialization.
The resulting increase of human investment in the environment,
in turn, anchored humans more and more closely to the
territory in which they chose to live. The symbiosis that thus
emerged between different landscapes and the life-ways
invented and constructed by human groups to deal with them
eventually narrowed the spectrum of adaptive options open to the
individual societies concerned, driving them to devise more and
more complex solutions with more and more unexpected
consequences.
Overall, therefore, increasing control over the material and
natural environment was balanced by increasing societal
complexity, which was not always simple to keep under control.
In summary, one might say that sociality, rather than mobility,
became the way to survive. A control loop emerged between
innovation and population density growth that was responsible
for an exponential increase in both over the last 10 000 years.
That control loop is summarized as follows:
problem-solving structures knowledge ! more knowledge
increases the information-processing capacity ! that, in turn,
allows the understanding of new problems ! this understanding
creates new knowledge!knowledge creation involves more
and more people in processing information ! this increases the
size of the group involved and its degree of aggregation !
increased group size creates more problems ! these problems
increase the need for problem-solving ! problem-solving
structures more knowledge . . . and so on.
The result of this loop was the continued accumulation of
knowledge and, thus, of information-processing capacity,
enabling a concomitant increase in matter, energy, and
information flows through the society; this, therefore, enabled
an increase in the number of people participating in that society.
As these societies integrated the activity of more and more
people, they became increasingly vulnerable to both internal
and external perturbations. These perturbations were of very
different kinds: externally, they comprised strong fluctuations in
temperature and precipitation, plant or animal epidemics, or
other sudden disturbances in resource availability, while
internal disturbances were often due to interruptions in energy
flow (causing shortages or even famines) or in information flow
(causing misunderstandings and social conflicts).
An important aspect of this increase in vulnerability is the
fact that human interaction with the environment shifted the
risk spectrum to which societies were subject. Each human
intervention in the environment substitutes unknown risks of
different frequency and magnitude for the risk removed.
Because the majority of risks removed are the most frequent
ones, human intervention in due course results in a shift in risk
spectrum from frequent, minor perturbations to less frequent,
larger ones. Ultimately, this will result in a kind of ‘‘risk barrier’’
(like a sound barrier), a point in time when a number of these
unknown, infrequent perturbations coincide and have an effect
that is commonly experienced as a ‘‘crisis.’’
The increase in vulnerability led to a rapid increase in the
investment needed to maintain societies and to suppress
centrifugal social tendencies and conflicts. Part of this
investment was needed to deal with the increasing need for
energy. Just to give the reader an approximate idea, whereas a
human being uses about 100 watts to maintain his or her
metabolism, as in the case of hunter–gatherers, in modern
society, average energy consumption per capita is about 10 000
watts. The hundredfold increase is essentially used to maintain
the cohesion of the social system.
The other component of that investment dealt with the
necessary increase in information flow, requiring and facilitating
the accumulation of knowledge to keep people interested in
being members of the society by providing them with
advantages and advances in dealing with their environment,
including each other and the material world. This is more
difficult to quantify, but it is no less visible if one compares the
material culture of early societies with that of modern societies
that dispose of millions of different kinds of artifacts. As each of
these artifacts reflects the particular knowledge needed to invent
and create it, their diversity is, in a way, a proxy measure of the
volume of knowledge available to the society. Seen from this
perspective, we may interpret this explosion in the diversity of
material culture as an indicator that innovation (accumulation of
knowledge) became the dominant driver of social evolution, and
energy supply and conflict became its main constraints.
What Happened during the ‘‘Urban Revolution’’?
This question can be divided into two components that are
relevant for the current argument, and I will deal with each in
turn. The first component is: What drove the emergence of towns
and cities? When measuring how city size scales over the long
term with a range of different indicators, the latter seem to fall
into three groups (8):
– The proxies for energy consumption scale sublinearly with
urban size, indicating that when cities grow, they become
more energy-efficient.
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– As is to be expected, the proxies measuring the size of the
population, such as the number of basic service providers
(e.g., bakeries and schools), scale linearly with urban size.
– Surprisingly, however, the proxies related to innovation and
new wealth creation (such as the number of patents or the
number of employees in research and development per
capita) scale superlinearly with urban size (i.e., they increase
faster than the population).
This research, therefore, seems to indicate that the driver
behind urban growth is innovation. Very tentatively, I propose
the following hypothesis to explain this very recent discovery.
Whereas invention (the realization of a new idea) is generally (at
least in history) the result of the effort of one person or a small
group of people and involves a limited number of cognitive
dimensions, innovation (the spread of such an idea throughout
a population) involves very many more people and cognitive
dimensions. Hence, innovation is favored by the coexistence of
many people in a relatively small space, in which they are, of
necessity, highly interactive. In short, cities favor innovation,
and innovation favors cities.
The second component of the question we need to consider
in this context is: How did towns and cities affect the (positive)
feedback loop between the increased need for problem-solving and
the growth of the human population? Van der Leeuw and
McGlade (9, 10) present us with a detailed discussion of this
question, which I will here summarize very briefly. First, towns
concentrated people in space, thereby reducing the time needed
to access most information, especially when, within such towns,
neighboring people were exercising similar activities and,
therefore, were most closely involved with each other in
everyday life. Second, the towns soon became foci of attention
for those in the society who were not living there—as
marketplaces, they became an important source of goods and
information for the surrounding countryside. In the process, the
trading of tokens, and eventually of money, was invented as a
means to communicate and store value and to facilitate material
exchanges. Third, in all urban societies, we see the development
of writing (or some similar means of accounting and communication,
such as quipu’s in Peru), which, on one hand, reduced
the error rate in communication and, on the other hand,
enabled communication by nonoral means across larger
distances. Fourth, in such early towns, we see the development
of an administration—that is, institutionalized channels of
communication and conflict resolution.
In summary, the conjunction between the absence of external
drivers toward urbanization on one hand, and the fact that
towns and cities facilitate communication in a major way on the
other, point to the emergence of urban systems as a nexus in the
development and expansion of information-processing and
communication networks in human societies. As a result, i)
dependencies were created between more and more distant
regions; ii) the number of people in individual aggregations
increased markedly; thus iii) causing increasing dependency on a
narrow spectrum of abundant and dependable subsistence
resources; iv) societies became more and more complex as a
result of task differentiation and specialization; and v) the
investment in the natural environment and in material culture
increased measurably. All of these, and other, aspects of the
urban revolution drove human social systems further and further
away from flexibility and rapid adaptation to environmental
change, while increasing the demands on the social system.
What Happened during the ‘‘Imperial Revolution’’?
As towns grew, so did their energy needs, as expressed in the
need for foods, raw materials, goods, fuels, and so forth. Not
only did this lead to increasing control (and the concomitant
exploitation) of towns and cities over the countryside surrounding
them, it also extended the trade and exchange networks
across larger distances. Ultimately, the size, importance, and
density of the networks needed to maintain the energy flow into
urban societies outstripped the size and density of the
information networks responsible for maintaining social stability.
Hence, cities in areas speaking different languages engaged
in increasingly intensive trade and exchange relations. Ultimately,
this created ‘‘empires’’—that is, geopolitical units
spanning different social, cultural, and linguistic entities.
To illustrate how this worked in practice, we could look at
the history of the Roman Empire (11). The expansion of the
Roman Republic was enabled by the fact that, for centuries,
Greco–Roman culture had spread around the Mediterranean
coasts. It had, in effect, structured the societies in (modern)
Italy, France, Spain, and elsewhere in a major way, leading to
inventions (such as money, the use of new crops, and the
plough), the building of infrastructure (e.g., towns, roads, and
aqueducts), the creation of administrative institutions, and the
collection of wealth. Through an ingenious policy, the Romans
aligned all of these advances and made them subservient to their
needs; in other words, they used these advances to aid the
uninterrupted growth of the flows of matter (wealth, raw
materials, and foodstuffs) and energy (slaves) throughout their
territories, toward their urban centers, and ultimately toward
Rome itself.
The Roman Republic and the Empire could expand as long
as there were pre-organized societies to be conquered. Once
their armies reached beyond the (prestructured) Mediterranean
sphere of acculturation (i.e., when they came to the Rhine, the
Danube, the North African deserts, and the Middle Eastern
empires), that was no longer the case, and conquests stopped.
Then they began major investment in the territory thus
conquered. This consisted of expanding the infrastructure
(e.g., highways, villae, industries) and the trade sphere (e.g., in
the Baltic and Scotland, but Roman trade goods have been
found as far afield as India and Indonesia) in order to harness
more resources.
As large territories were thus ‘‘Romanized,’’ these territories
became less and less dependent on Rome’s innovations for their
wealth, and thus expected less and less from the empire. One
might say that the ‘‘information gradient’’ between the center
and the periphery leveled out, and this made it more and more
difficult to ensure that the necessary flows of matter and energy
reached the core of the empire. As the cost of maintaining these
flows grew (in terms of maintaining a military and an
administrative establishment [12, 13]), the coherence of the
empire decreased to such an extent that it ceased, for all intents
and purposes, to exist. People began to focus on their own
interests and the local environment rather than their interest in
maintaining a central system. Other, smaller, structures emerged
at the empire’s edges, and there the same process of extension
from a core began anew, at a much smaller scale and based on
very different kinds of information. In other words, the
alignment between different parts of the overall system broke
down, and new alignments emerged that were more relevant
locally or regionally.
In this overall dynamic, cities played a major part. They were
demographic centers, administrative centers, and foci of road
systems; but above all they were the nodes in the network, the
locations where most information processing went on. As such,
they were the backbone of any large-scale human social system.
They operated in network-based ‘‘urban systems,’’ which linked
all of them within a particular sphere of influence. Such systems
had structural properties that derived from the relative positions
the cities occupied on the information-processing gradient and
in the communications and exchange networks that linked them
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to each other. Although the role of individual towns in such
systems did change (relatively) rapidly (14), the overall dynamic
structures were rather stable over long periods of time.
Because people congregated in cities, the latter harnessed the
densest and the most diverse information-processing capacity.
Not only did this relatively high information-processing capacity
ensure that cities were able to maintain control over the channels
through which goods and people flowed on a daily basis, but
their cultural (and, thus, information-processing) diversity also
made them into preferred loci of invention and innovation.
The superlinear scaling of innovation with city size (see
above) enabled cities to ensure the long-term maintenance of the
information gradient that structured the whole system. It was
due to a positive feedback loop between two of any city’s roles.
On one hand, most flows of goods and people passed through
towns and cities, supplying them most intensely with information
about what was happening elsewhere, and again, this
enhanced their potential for invention and innovation. But the
same connections enabled cities to export these innovations
most effectively—exchanging some part of their informationprocessing
superiority for material wealth.
CONCLUSION: FROM ‘‘POPULATION THINKING’’ TO
‘‘ORGANIZATION THINKING’’
Let us now come back to the theme that inspired this
colloquium and my contribution to it. What are the fundamental
implications of the processes I have just outlined? What is it
that changed in the human way of dealing with the environment
during the Holocene? In this paper, I argue that in the
Holocene, environmental ‘‘crises’’ are triggered by both social
and environmental changes or (most often) by a combination of
both. The fundamental change is one from humans responding
to environmental change and disruption by migration to
humans investing in the environment, and therefore responding
to environmental change by problem solving. As the challenges
involved demanded more and more cooperation and interaction,
the survival of these human groups no longer depended on
their mobility, but on their sociality. One therefore needs to
look at the combined socio-environmental systems over the
longer term to understand them. In particular, one must
consider the second-order changes (the ‘‘change of change’’)
that reflect the buildup and culmination of the shifts in the
social and environmental risk spectra that are due to the
human–environmental interactions in periods before the ‘‘crisis’’
occurs.
Hence, we have to change our way of thinking about
environmental ‘‘crises.’’ They are not exceptional; they are,
rather, a fact of life in any society’s interaction with its
environment. There is no sedentary human occupation without
environmental degradation. Rather than seeing such ‘‘crises’’ as
external perturbations, which require a response that either
changes the environment or the dependency of the society on
the environment (i.e., exploitation of new resources), they
should be seen as (temporary) incapacities of the society to
process the information required to deal with the dynamics with
which they are confronted. In other words, they should be seen
as ‘‘social’’ challenges rather than ‘‘environmental’’ ones. These
challenges generally occur because the society in question has
invested so much in a particular way of life that it cannot
innovate itself out of difficulty before time runs out. In the
Roman case, for example, such a huge area and so many people
had been so intensively adapted to a particular way of life, and
for so long, that changing the society’s relationship with the
environment would have taken way too long.
The solution to such challenges is to be found in the
reorganization of the whole way of life and worldview of such
societies, rather than in the (modification of the) environment.
This implies that we have to implement a major shift in thinking
about socio-environmental issues, from ‘‘population thinking’’
to ‘‘organization thinking’’ (15). In this perspective, a crisis does
not imply the disappearance of the people involved, but a
transformation of the organization that links them. Climatic
and environmental factors are no longer to be seen as the causes
and sole drivers of the disequilibria observed. Rather, the
balance between the investment and the innovative capacity of
the society determines whether a solution can be found to the
challenges the environment poses or not. In that context,
internal tensions and perturbations increasingly become important
alongside external ones because such internal tensions and
perturbations affect the ease with which the societies in question
are mobilized to deal with the challenges they face.
The new element in very recent times is the almost unbridled
acceleration of innovation and change, which at first sight could
help us avoid the worst of the looming problems. However, for
that to work, we would also need to accelerate the ‘‘change of
change,’’ and redirect it to a sustainable vision of our
relationship with the environment. For the moment, that is
not really the case. For example, a recent EU report proposes
huge investments to adapt to climate change, including moving
entire cities away from the coastal zone. The effort involved will
inevitably be so costly as to render impossible the investments
needed to mitigate climate change. Hence, this is an example of
an older attitude applied to the emergent problems of the
environment: let’s find a (traditional) technological solution
that adapts to the ‘‘inevitable,’’ rather than using our
technological inventiveness to drive society into a fundamentally
new kind of interaction with the environment.
The same thing is essentially happening in the Arctic, where
climate change has now opened up both the Northwest and the
Northeast passages, and where this year sees all bordering states
(Russia, Canada, and the US mainly) preparing themselves for
a rush to grab as many of the resources hidden under the ice as
possible, simply to maintain the current socioeconomic system a
little longer.
As argued beautifully in Leonardo DiCaprio’s recent film,
The Eleventh Hour, what is needed is a fundamental mental and
cultural change that acknowledges that, even if the problems are
environmental, the only way to deal with them is to change our
attitude, our vision of the future, and the decisions that we
make to realize that vision. If we stay on the course we have
now been on for several centuries, we will not destroy our
environment (which will survive us), but we will destroy the
fabric of our own societies, and thus our species (which can no
longer live without the structure provided by society).
From that perspective, it is distressing that the sustainability
movement that is now rapidly taking hold of the business and
political communities is essentially a reaction to what we do not
want, rather than a movement guided by a vision of the kind of
future we would like to create for our species.
References and Notes
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Atlantic Ocean during the past 130,000 years. Quaternary Res. 29, 142–152.
3. Bond, G.C., Showers, W., Elliot, M., Evans, M., Lotti, R., Hajdas, I., Bonani, G. and
Johnson, S. 1999. The North Atlantic’s 1–2 year climate rhythm: relation to Heinrich
events, Dansgaard/Oeschger cycles, and the little ice age. In: Mechanisms of Global
Change at Millennial Time Scales, Geophysical Monograph 112. Clark, P.U., Webb, R.S.
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French).
15. Lane, D.A., Maxfield, R., Read, D.W. and van der Leeuw, S.E. From Population
thinking to organization thinking, chapter 2. In: Complexity Perspectives on Innovation
and Social Change. Lane, D., Pumain, D., van der Leeuw, S.E. and West, G. (eds).
Springer (Methodos Series), Berlin. (In press).
Sander E. van der Leeuw is at the School of Human Evolution
and Social Change at Arizona State University. His address:
School of Human Evolution and Social Change, Arizona State
University, PO Box 872402, Tempe, AZ 85287-2402, USA.
E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it
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