It is not difficult to realize that the world around us is vast and complex, its dynamics happening somewhere in the fascinating but paradoxical realm of complexity, beyond the easier to envision extremes of complete order or chaos. It is no coincidence then that one of the pleasures of life is to grasp some aspect of the Universe, be it through the cosmovision of some philosophy, or using advanced computer models.

In everyday life, though, we are not roaming the world hooked to a supercomputer with just the appropriate set of equations to understand every single situation happening around us. No matter how rational and knowledgeable we believe we are, we rely heavily on intuitive mental models, imprinted upon us by our education and culture, to make sense of life and express our impressions about it. We are forced to face, evaluate and act on complex situations based on more or less blurry ideas and incomplete information. These mental models almost always have some irrationality built into them, something that is particularly true when we assess the multidimensional and multi-scale problems related to the global environment and sustainability.

These issues are nicely highlighted in the book Panarchy. Understanding Transformations in Human and Natural Systems [1], a thoughtful book edited by Lance H. Gunderson and C.S Holling, and published in 2002. In chapter 1 of this book “In quest of a theory of adaptive change“, Gunderson, Holling and Ludwig present a clever picture of some common mental models used to understand Nature and justify our approach to it. These authors call these five models “caricatures”, or “myths”, simple metaphors expressed as balls rolling in different landscapes and encapsulating our ideas about the dynamic behaviour of the world. None of these models is completely right, nor completely wrong, but all are just incomplete visions of one and the same world.

Myths of nature. Inspired in and redrawn from: "In quest of a theory of adaptative change", Gunderson, Holling & Ludwig, 2002
Myths of nature. Inspired in and redrawn from: “In quest of a theory of adaptative change”, Gunderson, Holling & Ludwig, 2002

The first model, “Nature random” or “Nature flat“, expresses the worldview of a nature without feedbacks or nonlinearities. Changes in this world are driven by random causes, natural or political, and it is therefore a world where humans can do as they please to satisfy their needs, with no risk of triggering undesirable irreversible processes. The ball just moves in a flat terrain, going wherever some random force pushes it.

Nature stable” expresses the view that the world is largely in balance, a static world dominated by negative feedbacks equilibrating any change. This is the worldview that emphasizes maximum yields and believes that we can optimize things to navigate turbulent times.

Nature unstable” or “Nature anarchic” is the opposite worldview, where Nature is in delicate balance and extreme caution is needed not to push it away from it. This is the mental model where the precautionary principle dominates, and is the worldview held by many environmental organizations.

Nature Resilient” is a step forward in our understanding of Nature, it encompasses the previous three views. It relies on the lessons from the science of complex systems and dynamical systems applied to natural science. A resilient world is one in which several dynamical basins of attraction exist, where a given part of nature might be forced to move to a neighbouring basin by human intervention, or by changes in variables at larger scales of time and space. In this worldview, a perturbed ecosystem can flip to a different state, a move that is fully admissible under the prevailing environmental conditions, although possibly unknown and probably not pleasant for its inhabitants and users. An example of this is the often observed transition of grasslands to dry unproductive woodlands due to heavy overgrazing (Australia, Patagonia).

Nature evolving” is presented as the last frontier. It depicts an even more complex world than “Nature resilient”, one where the dynamical landscape changes with time. Gunderson, Holling and Ludwig convincingly argue that this view might be the one closest to our real world, and the one that we should be exploring to assess our impacts on Nature and evaluate our chances for long term survival in the Anthropocene. It is also the one worldview that is least accessible to our intellects, the one that poses the greatest challenges to understanding and prediction, where intuition might not longer serve us so well.

I believe that these models capture wonderfully well some of the most common sets of beliefs that people use to summarize and classify the behaviour complex natural systems. Even if they are just overly simple caricatures, they also show us that having a look at our often unchallenged mental models can be a worthy exercise that can teach us lessons on how to approach Nature in more harmonious ways.

Now, read again the myths. Which is the one closest to your beliefs?

[1] Gunderson, Lance H., and C. S. Holling, eds. Panarchy: Understanding Transformations in Human and Natural Systems. Island Press, 2002.

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