The most influential force in the world is the idea. Gods, priests, kings, dictators, democrats, terrorists, anarchists all need an idea to justify themselves. It is on the strength of one idea that we once believed that the world was flat and scientists had to work hard to prove that it was actually round. We again believe in a flat world from a completely different perspective.

It is on the strength of the idea of nationalism that we fought two world wars and killed over a hundred million people. It is on the strength of the idea of nationalism that large segments of the world�€™s population gained freedom from their colonial masters. The idea of evolution drives scientific research today. The idea of post-humanism may drive scientific research tomorrow.

In the last century, the ideas of capitalism and communism competed with each other to dominate the human mind. Also, the idea of freedom and authority competed with each other at the same time. Many people bracketed capitalism with freedom and communism with authority, though capitalists supported authoritarian regimes in Panama, Chile, El Salvador, Pakistan, Congo, the Philippines, among other countries while communists supported freedom movements across Asia and Africa. Francis Fukuyama proclaimed the permanent victory of democracy and free market (representing freedom and capitalism) in the world as the Berlin Wall collapsed in Europe, even though vast tracks of Latin American, African and Asian continents were still ruled by dictators and economies. Obviously to some people in the West, including an honorary Westerner like Fukuyama, the West was the world. No wonder the West was attacked, giving birth to the idea of clash of civilizations. Obviously to some people when the West is attacked, civilizations clash. When the West attacks others, it is just boring colonisation.

While the conflict between freedom and authority and capitalism and communism is still not solved in at least two third of the world, one idea seems slowly to unite a growing number of people from north and south, east and west. It is the idea of sustainability. I would personally credit the Club of Rome for raising the question of sustainability through its Limits to Growth. Never mind that computer projections about future resource supplies have been proved wrong. The underlying idea that growth is not sustainable with an infinite assault on the earth�€™s resources has seized people�€™s imagination. It encourages villagers in Himalayas to hug trees to save them from timber companies. It encourages Wangari Mathai to plant a million trees and Al Gore to give a thousand presentations on climate change. It has led to a treaty on emissions (even though it may not have been signed by the world�€™s largest emitters), triple bottom-line auditing, clean-tech investments, green technologies, renewable energies and eco-tourism. It is slowly leading to a change in our lifestyle.

The idea of sustainability is so far understood in the environmental context. The practices that lead to environmental damage also often lead to social conflicts and violence �€“ ask farmers in China and India or Sudan and South Africa. Stein Tonnesson, director of Peace Research Institute Oslo, fears that in future we may see environmentally driven trade wars. Others worry about conflicts over water and emissions. We may see the concept of sustainability expanding as linkages between climate change and social change are better understood.

We can expect sustainability to be the dominant idea of the second decade �€“ perhaps also the third decade - of the 21st century. Will it be the idea that dominates most of the 21st century? I doubt it.

The sustainability idea is perhaps the last idea that concerns the human civilization that we know today. In the second half of this century, science and technology may change the very nature of humanity through dramatic developments in outer space exploration and GNR technologies (genetics, nano-technology and robotics). Human being of tomorrow may not be human being at all. They may be artificial designer humans or some combination of humans and machines. They may be able to go deeper into space and perhaps live there. They may even be able to connect to other beings in other galaxies. The issues we will debate then will be very different from the issues we debate today.

I don�€™t know which ideas will dominate in the world where humans co-exist with post-humans. I just hope that such a new world �€“ which I will not be around to see �€“ is different from our world in one very fundamental way. All the ideas that humans have developed so far �€“ perhaps with the exception of sustainability �€“ are ideas that compete for dominating the world. Thus, underlying all such conflicting ideas is the idea of dominance. If sustainability takes a deeper root from its current scope, it may finally compete with the idea of dominance that has characterised human history. If it does not and if somehow the human race still manages to move to the world of human and post-human co-existence, desire for dominance might convert human being into demons. The big question before us is not so much which idea will dominate the 21st century. It is whether we can challenge the idea of dominance and save humanity.