Chandran Nair: Founder of Hong-Kong based think tank Global Institute For Tomorrow (gift)

The extreme form of capitalism which has permeated the world, particularly in the last 30-40 years, is in deep trouble and we are in denial.

It is important to understand that fundamental principles of capitalism - that human beings are rational and markets behave rationally, and that markets will assign prices - are flawed.

It is also important to understand the roots of modern capitalism.

You could argue that slavery was the first attempt to under-price resources. When slavery came to an end there was colonisation, which was again an attempt by the capitalist model to use resources cheaply. With the end of colonies, we had the globalisation argument of economic growth and then the globalisation of finance.

“Capitalism has essentially hit a wall and a very different conversation needs to take place”

When I speak about this in Europe, they say there has been 30 years of over-leverage, but I say they should multiply that by 10 and look at 300 years of essentially exploited growth.

What we need to recognise now is that the world is a very different place from what it was 100 years ago when we had one billion people. With a current population approaching seven billion, things will have to change.

A fundamental issue that the world will have to recognise, and which Western capitalism has conveniently ignored, is that the goods and services which companies and economies seem to thrive on are based on under-pricing resources and externalising costs.

That game is over and we need a fundamental restructuring - essentially about how people will live, and we need to move beyond simple notions about growth to more sophisticated, nuanced discussions about human progress.

That is not the same as suggesting that economic growth will be able to deliver i-toys and cars to everyone. This is not possible and that is where capitalism has essentially hit a wall and a very different conversation needs to take place.

Professor Tim Jackson: Author of Prosperity without Growth - economics for a finite planet

Every society clings to a myth by which it lives.

Ours is the myth of economic growth. For the last five decades, the pursuit of growth has been the single most important policy goal across the world. The global economy is five times the size it was half a century ago. If it continues to grow at the same rate it will be 80 times that size by the year 2100.

This extraordinary ramping up of global economic activity is without historical precedent. It is totally at odds with the finite resource base and the fragile ecology on which we depend for survival.

Most of the time, we avoid the stark reality of these numbers. Growth must go on, we insist.

“The days of spending money we do not have on things we do not need to impress people we do not care about are over”

The reasons for this collective blindness are easy enough to find.

Western capitalism is structurally reliant on growth for its stability. When growth falters - as it has done recently - politicians panic. Businesses struggle to survive. People lose their jobs and sometimes their homes. Questioning growth is deemed to be the act of lunatics, idealists and revolutionaries.

Yet question it we must. The myth of growth has failed us. It has failed the two billion people who still live on less than $2 a day. It has failed the fragile ecological systems on which we depend for survival.

But economic crisis presents us with a unique opportunity to invest in change. To sweep away the short-term thinking that has plagued society for decades. To engage, for instance, in a radical overhaul of dysfunctional capital markets.

Untrammelled speculation in commodities and financial derivatives brought the financial world to the brink of collapse just three years ago. It needs to be replaced by a longer, slower sense of capital.

Fixing the economy is only part of the battle. We also have to confront the convoluted logic of consumerism. The days of spending money we do not have on things we do not need to impress people we do not care about are over.

Living well is about good nutrition, decent homes, access to good quality services, stable communities, satisfying employment.

Prosperity, in any meaningful sense of the word, transcends material concerns. It resides in our love for our families, the support of our friends, the strength of our communities, our ability to participate fully in the life of society, a sense of meaning and purpose in our lives.