It's all in the balance

These are already challenging - and exciting - times for higher education, but demographic changes are about to raise these challenges to a new level.

Population growth in itself is no longer the key issue: worldwide, the number of children per woman has now fallen to the magical figure of 2.1, so after the current cohort of under-15s has worked its way through the system, the global population is forecast to stabilise at around 9 billion by the middle of the century.

The real and most relevant change is the unprecedented and rapid rise in the number of middle-class people. In 2000, there were about 1 billion members of the middle class (defined by the Organisation for Economic Cooperation and Development as those who spend $10 to $100 a day). By the end of this year there will be an estimated 2 billion. And by 2030, projections suggest that the number will approach an extraordinary 5 billion.

This is obviously good news for human well-being. But, inevitably, it will also mean a massive rise in expectation and it is hard to see how the planet can deliver this. Key resources such as food, energy, water, minerals and even education are already in relatively short supply and will become increasingly scarce as demand escalates. Our use of fossil fuels, agricultural practices and the destruction of forests are already having major environmental impacts, making the situation worse.

If we are to continue to improve human well-being without coming up against a planetary "brick wall", we urgently need a new paradigm, based on science, technology, innovation and imagination. I believe that universities can play a significant role in developing this paradigm in three important ways.

The first, of course, is through teaching. Our higher education institutions are crucibles for creating both new leaders and improved cultural understanding.

When I look at the world's capacity for global decision-making I feel dispirited. The United Nations was formed in a period of idealistic thinking about the future, but its standing in the world has never been lower than at the present time, when it is most needed. We require a renewed sense that our cultures are more alike than they are different, and that our destiny on this planet is truly a shared one. The opportunity that higher education provides for the world's brightest and best to rub shoulders and develop a shared understanding will surely be crucial in this endeavour.

The second role for universities is in developing ideas to move beyond our current, broken model.

In the initial development of our capitalist society, we did not sufficiently appreciate the impact of indiscriminate use of the "global commons" - the Earth's ecosystem we share and depend upon - and the surplus value developed by capitalism was reinvested in infrastructure, in the UK and across the Commonwealth.

In the second phase of capitalist development, the expansion of economies has been defined almost entirely through consumerism in developed countries. We now know that this path leads to disaster.

What is the third phase in economic development? Academics around the world need to address this question, and the answer will strongly affect our shared destiny.

But universities cannot do this in isolation. The third - and perhaps most important - role for institutions of higher education involves new levels of engagement with the outside world. Universities will need to develop much smarter tools with which to do this. It is engagement with policymakers, private-sector companies and civil society that will determine the world's future direction. While there is superb leadership from certain businesses, policymakers and public-sector organisations, I see the process stalling precisely because it is disconnected.

Universities can provide a safe space where businesses and politicians can leave behind competitive advantage or political posturing and discuss common objectives. They are not committed to any private-sector company's profit or political line and so provide both neutral ground and the academic rigour needed to test the emerging approaches.

We can no longer afford to be ivory towers. Instead we should be brokering these relationships and fostering grown-up approaches to the resource challenge.

The imperative for action could hardly be stronger. If we continue on our resource-hungry path, all will suffer the consequences. But if we rise to this challenge, our generation is in a unique and decisive position to determine a positive way forward. Perhaps for the first time in human history, we have the opportunity not just to share our destiny but to shape it - and the role of universities could be pivotal.