The Education for Sustainable Development (ESD) literature is uplifting, full of fine ideals and the hope of creating a better world. The values implied are positive, optimistic and democratic; ESD is clearly a ‘good thing’. It would be mean spirited indeed to complain about this: who can criticize such a virtuous agenda? But herein lies a problem, for it may be precisely because it does not offend that ESD avoids the most difficult dilemmas facing our global society. Those dilemmas involve sharply contested views and disagreements concerning fundamental principles. Dealing with such conflictual areas is enormously challenging within education settings. Yet resolving these conflicts may well be the key to unlocking the apparently intractable problems of sustainable development. To highlight the importance of controversy in arriving at sound policy, below I analyze three of these contested areas—there are, of course, others.
First, questions surrounding population and overpopulation remain extremely sensitive. There are cogent arguments that the current human population already exceeds the earth’s carrying capacity. If that is the case, policies to reduce and then stabilise population are urgently required. But critics of this view argue that it is based on erroneous Neo-Malthusian assumptions, while there is also strong opposition to population control from some religious institutions. Meanwhile, the total population continues to grow towards seven billion, while estimates of sustainable population levels vary from less than two billion to more than fifteen.
Second, the role of science is more controversial than at any previous time in the modern era. Science and technology have brought enormous benefits, but are also seen to contribute to—or even underpin—many of our greatest problems. Although Ecological Modernisation theory and ‘bright green environmentalism’ see technology as the answer to many environmental problems, science itself has lost much of its legitimacy and is widely viewed as elitist and exclusive. Recent controversies, such as those surrounding climate change emails, accentuate the need for scientific transparency. Can sustainable development occur without changing the nature of science and societal views about science? Should Sustainable Development embrace a Post Normal Science approach that makes participation and social learning central objectives?
Finally, and perhaps most crucially, is the dilemma concerning the nature of Sustainable Development itself. Can it occur within the current consumptionist, growth-based paradigm? Or can it only come about if we return to the idea that there are indeed limits to growth, and that fundamental laws of ecosystem energy and material cycling necessitate that current levels of resource exploitation cannot be maintained in the long-term? (See Barry 2009; Singer 2010). If real (that is, sustainable) prosperity precludes continual economic growth, how can individual psychology and collective political structures cultivate a fundamentally different paradigm?
There is a danger in being too inoffensive. It can create a climate which gives rise to concern that by even raising such sensitive issues ESD practitioners will be seen as being biased. But as Cairns (2002) argues, environmental questions cannot be addressed purely through consideration of ‘objective’ science alone, but must take account of opinions, values and beliefs. Furthermore, if ESD does not even allow for such difficult problems to be addressed, then it is by default complicit in maintaining a status quo that is, fundamentally, unsustainable (Gadotti 2008). Yet the UNESCO review of the UN Decade of Education for Sustainable Development almost entirely neglects these issues (UNESCO 2009). If ESD fails to address these topics because they are controversial, then it will fail to prepare future generations to be adequately prepared to tackle them. At the very least these issues should be part of any ESD agenda, although it can be argued that for many of these problems Education cannot be neutral, but necessarily has to find its own positions within increasingly polarised debates.
Barry J (2009) ‘Choose life’ not economic growth: critical social theory for people, planet and flourishing in the ‘age of nature’. Nature, Knowledge and Negation: Current Perspectives in Social Theory, Volume 26, 93–113.
Cairns, K (2002) The legitimate role of advocacy in environmental education: How does it differ from coercion? Ethics in Science and Environmental Politics, 2002, 82–87.
Gadotti, M. (2008) What We Need to Learn to Save the Planet. Journal of Education for Sustainable Development 2:1 : 21–30.
Singer, M. (2010) Eco-nomics: Are the Planet-Unfriendly Features of Capitalism Barriers to Sustainability? Sustainability 2010, 2, 127-144
Unesco (2009) Learning for a Sustainable World: Review of Contexts and Structures for
Education for Sustainable Development (Unesco, Paris) http://unesdoc.unesco.org/images/0018/001849/184944e.pdf 
Learning for a sustainable world