It is not one's absolute nor even ultimately one's relative level of wealth that really matters when it comes to well-being in the so-called 'developed' world today.
What would a post-growth world look like? Some would argue that it is not difficult to imagine a world without growth, as many countries are already living in it.
Japan stagnated for a decade and its economy has been left hollowed-out. Much of Europe is in negative or near-zero growth in the wake of the global economic crisis, and in none of these countries can a lack of growth be viewed as a good thing.
We see before our eyes the human cost of economic systems that are dependent on constant growth to function. We currently rely on growth for all kinds of purposes. As a substitute for the redistribution of wealth, for example - so long as everyone is getting richer, why worry if some are getting much richer than others?
When the music stops ...
But when the growth machine falters, or stops, millions lose their jobs, tax revenues fall, governments embark on 'austerity' programmes that only deepen the calamity, laying off public sector workers or cutting their wages, while public services and social security systems collapse.
Underlying this problem is the banking system itself. Most money in the economy is created by commercial banks as they advance credit, something they are very happy to do in boom times. But when the economy hits trouble, they call in loans and restrict new lending.
In turn this reduces the volume of money in the economy, so there's not enough money for all existing lenders to service and repay their old debts, and the crisis only grows. And the banks find themselves - as in a Loony Tunes cartoon - running in the air when they have already stepped over the edge of the cliff.
Let's do it by design, not accident
The point now, therefore, is to transition from an accidental no-growth economy to a deliberate no-growth society.
We plainly cannot guarantee growth, as even mainstream economics is coming to accept there will never really be an end to boom and bust. Even if we could, would we want to?
As we emerge from recession, there are for the first time over one hundred billionaires in this country - more per capita than anywhere else in the world. They have exploited the crisis for personal gain, many benefiting from the Bank of England's 'stimulus' policy of quantitative easing.
Capitalism, as Thomas Piketty has recently powerfully shown, is an engine for - indeed a guarantor of - inequality. Just as much in recession or 'stagnation' as in growth. Growth-oriented capitalism is a tool of the uber-rich, whether or not it actually achieves growth.
Now, how many planets have we got?
For the rest of us, 'growth' involves the destruction of vast swathes of our natural world, including the balance of our atmosphere. Growth is founded on unbridled consumer culture, in which we are encouraged to "spend for Britain" so that the economy can grow fat off our personal debts.
But we are currently living as though we had three planets. It is impossible for us to consume at our current rate and survive; economic growth is founded on that rate of consumption.
We are thus inevitably entering a post-growth world. The task now is to enable people to understand that deliberate post-growthism represents a viable, necessary and in fact desirable approach to our flourishing on this planet, so that we can move towards a positive vision of that future.
It's the Ecology, stupid!
The first step is to start talking less about "the economy". Such talk mostly just feeds into people's pre-existing stereotypes of what an economy is.
It reinforces the belief in the economy as the cart not the horse, encouraging us to construct our systems of employment, education, social security and health in the way most conducive to GDP growth, ignoring why we actually have such systems.
We should talk more about the things that an economy is actually for: producing a better quality of life for individuals and a healthier and happier society. Whether or not economic growth is taking place is a question unrelated to whether these aims are being achieved. Our task is therefore is to re-embed talk of the economy within deeper frames, as Karl Polanyi has articulated: those of society and ecology.
If we can move away from talking about 'standard of living', which is benchmarked against a consumerist hierarchy of goods, and towards talking about 'quality of life', which refers only to the lived experience of satisfaction, then we will also see how a concern for ecology replaces a concern for economy.
As Richard Layard's work and the New Economics Foundation have been so instructive in affirming, a well-being agenda leads to recognition of the value of ecology, and with it the realisation that a post-growth society does not mean a lower quality of life, but a better one.
Enough, is enough
This may still sound very abstract. Why should people wish to move away from goods as a source of satisfaction? Crucial to this question is the connection between equality and quality of life.
As is now familiar to us all, from Wilkinson and Pickett's work, it is not one's absolute nor even ultimately one's relative level of wealth that really matters when it comes to well-being in the so-called 'developed' world today. On virtually every measure, it is the degree of inequality across society as a whole that counts.
Once we overcome a certain threshold of absolute privation - and the growing need for Food Banks in this country shows us we cannot disregard the threshold - having more goods is simply not going to improve our quality of life.
Social pressure creates 'need'
In 1776 Adam Smith declared leather shoes "a necessary of life in England", such that "the poorest creditable person" would be "ashamed" to be without them.
In the summer of 2011, we saw shoe-shops looted on the streets of London. Smith correctly saw that social pressure rather than demonstrable need determines whether goods are deemed necessary.
Consumer culture has nurtured these pressures, setting up a poisonous dialectic that has snowballed out of control, upsetting both our psychological balance and our societal stability.
It is therefore imperative now that we build a sense of enough, an end to the materialistic culture that always demands more and marginally better goods.
A creative commons - let's talk about sharing
Deep down, we all know growthism's dirty little secret: that it's a substitute for real fairness - a more equal society, and serious redistribution of wealth.
Liberal / neo-liberal economics was sold to us on the promise of 'trickle down'. And when socialists abandoned hope of achieving socialism, the empty promise was all they had left.
One approach to abandoning our faith in 'trickle-down', an absolutely necessary abandonment, is expressed in the following thought: Common sense will in the future become 'commons-sense'.
The quest for endless new frontiers to turn into 'resources' and commodities, the quest for speculative profit, the quest for accumulation: all of these can be turned back by a return to living on and in the commons.
Production on the commons simultaneously overcomes the systemic pressure for to produce unnecessary commodities, the need for constant expansion stimulated by competition, and the alienation caused by living as an economic atom.
By reclaiming the commons, we will revive the public and the social, giving us a renewed since of our interconnectedness with our environment, our locality, of our finite nature, and of the hubris - and nemesis - that awaits any lack of such awareness.
The concept of the commons is an ancient future that awaits us. It is what lies beyond the limits to growth.
The 'leisure society'
One of the many rewards will be the proper valuing of leisure. The pressure for growth has forced us to abandon leisure as a value in its own right, except insofar as it can be monetised through expensive holidays for two weeks of the year.
In a post-growth society, leisure will be a value distinct from, and not exchangeable for, the value of goods obtainable through work.
Greens should be wary of putting all their eggs in baskets marked 'jobs'. Employment needs to be shared out - most of us need to work less, and in less alienated settings. In Britain at least, time poverty is a more widespread problem than absolute poverty.
With more time will come a greater appreciation of the value of the natural world, which we are currently to busy to notice being eroded. We will have more time for thought, for our health, and for community.
There is, I believe, a substantial audience for thinking such as this. There are swathes of people in the green movement and far larger swathes beyond who feel that there must be a way of speaking inspirationally, and a way of being that reveals in a meaningful way our care for future generations and for all our fellow beings.
For us as a movement, and ultimately as a nation and a species, to be calling for enough to be done so that human beings can survive is now essential - for us to survive, and flourish.
Rupert Read is Green Party Transport Spokesperson, and lead MEP-candidate for the East of England at this year's European Elections. Website: www.rupertread.net. Twitter: @GreenRupertRead (political) or @RupertRead (personal).
See Rupert's new report: 'Post-growth Common Sense: Political Communications for the Future', published this month by the Green House Think Tank.
More articles by Rupert Read on The Ecologist.