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Skip to 0 minutes and 5 secondsIn Venezuela, Alexander von Humboldt climbed the Chimborazo volcano, thought at the time to be the world's highest mountain. There, in 1890, he also sought the disastrous environmental effects of colonial plantations, cash crops, monoculture, irrigation, and deforestation. Humboldt wrote about the harmful effects of human-induced climate change, about the degrading of the land and atmosphere by deforestation and erosion, how pearl fishing had depleted the stocks of oysters. Towards the end of his life, he even prophetically warned about deleterious gas emissions at industrial centres. There were moments when he was so pessimistic that he painted a bleak future of voyages into space, where humans would spread their lethal mix of vice and greed even across other planets.

Skip to 1 minute and 5 secondsOn the 25th of January, 1995, the level of the River Maas, or Meuse, started to rise dangerously in the south of the Netherlands. Two days later, 75,000 people were evacuated from the region between the dikes on the Meuse and the Rhine, later increased to nearly a quarter of a million. The extensive flooding was the worst for 60 years, although not as catastrophic as it might have been had the dikes failed completely. The response has been a reversal of previous policies to contain the river. Instead, in a $2.8 billion project called Room for the River, dikes have been pushed inland, floodplains restored, and built obstacles, and in some cases, whole towns have been moved.

Skip to 1 minute and 58 secondsWorking with nature in this way has increased the carrying capacity of the rivers and restored environmental quality. In contrast, here we see the inside of a nuclear reactor building. The operation and safety of this plant relies on every detail of the engineering. Every eventuality must be taken into account, every component must normally operate within its safety margin, and every possible failure must be planned for. There's no question of working with nature. Here we have to have complete mastery. And we do, because the engineers have designed the plant from the bottom up. Here, however, is an experiment called Biosphere 2.

Skip to 2 minutes and 49 secondsThe scientists have tried to reverse engineer part of our natural world, which they call Biosphere 1, and create an artificial living environment. The species of plant and animal and seven humans were selected to form a closed system. As is well known, the experiment is described as having failed, when it had to be brought to a premature close to avoid risks to life. To my mind, the experiment was a great success in demonstrating the complexity of an ecosystem. The properties and behaviours that emerge when we put together a subset of a complex system may not be anything like those of the complete system.

Skip to 3 minutes and 39 secondsIn the contrast between the nuclear reactor and Biosphere 2, and in the different approaches to controlling the Meuse River, we see the difference between things that are complicated and, in its technical meaning, systems that are complex.

Examples of complexity

In this video we look at the link between sustainability and complexity to understand what it means to say that sustainability is a complex problem. I begin by introducing the 19th century geographer, naturalist and explorer, Alexander von Humboldt, who was the first to warn of the dangers of distorting or destroying Nature for the benefit of humans, even though he was unaware of the scale on which this would subsequently happen. His vision of the danger was based on an appreciation of the complexity of interactions in Nature, interactions that could not be wilfully disturbed without unintended consequences.

I look next at a project where, from a natural disaster - the floods in Maas in the Netherlands in 1995 - we have learnt how to work with Nature, not against it. Here we see that a simple engineering solution failed and a more nuanced approach to the complexities of flood defences was required.

On the other hand, something like a nuclear reactor is complicated but is not complex in the technical sense. One of the important learning outcomes of this week will be to understand the difference. It is partly that in principle, we understand every detail of a reactor and how every element is designed to work. Its safety relies on this. Complex systems on the other hand work to no such master-plan.

When we try to put together a natural system from scratch in the hope that we understand every detail, we may fail. Biosphere 2 was just such a project.


Watch the video and, in the discussion area, share your understanding of the difference between ‘complicated’ and the technical sense of ‘complex’.

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This video is from the free online course:

Concepts in Sustainable Development: An Introduction to the Key Issues

University of Leicester

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