We tend to think that societies are either capitalist or not, class societies or not. But ignoring the smaller differences means we fail to see one of the most important processes shaping human sociality.
Historically, or prehistorically, human beings have lived in everything from the most egalitarian hunting and gathering bands – based on food sharing and gift exchange – to the most tyrannical dictatorships.
Although all the modern “market democracies” of the developed world may appear to occupy a similar place on that continuum of inequality, there are in fact crucial differences between them which tell us a great deal about how societies work and about how our social potential is realised.
I have worked for several decades doing research on social class differences in health and life expectancy as well as on the effects of different degrees of income inequality.
The gap in life expectancy between people in “professional” jobs and those in unskilled manual jobs is now almost five years for women and over eight years for men.
Huge swathes of the population are simply deprived of a substantial proportion of life – undoubtedly the greatest human rights abuse in developed societies.
One of the patterns that has emerged is that it is not the richest of the developed countries which have the best health, but the ones with the smallest income differences between rich and poor.
The United States, which is the most unequal of the developed countries, comes in at about number 26 in the international life expectancy league table.
Despite being richer than other countries and spending much more per head on medical care than any other country, it does less well than most of the rest of the developed world.
Countries with the highest life expectancy are more equal societies like Japan, Norway and Sweden.
Homicide rates and levels of violence have a similar pattern. So do rates of imprisonment. Even the educational performance of school children (as measured by international maths and literacy scores) is better in societies where income differences are smaller.
More equal societies are marked not only by better health, less violence and better educated kids, but also by lower teenage birth rates, higher levels of trust, stronger community life, and even lower rates of obesity.
Britain is amongst the more unequal of the developed countries. Because of this we suffer more from almost all the problems associated with relative deprivation.
Health is less good than elsewhere in western Europe, levels of violence, teenage births and imprisonment rates are high, and social mobility is lower than it was a few decades ago.
While the Blair government has begun to reduce rates of child and pensioner poverty, inequality went on increasing during its first three years in office.
As a result, it has only just got back to the levels of inequality which existed when it came to power in 1997. It has failed to reverse any of the increase in inequality which took place under Thatcher and Major.
People – particularly socialists – have always thought that inequality was socially corrosive. And modern data shows that there are heavy human and social costs of even small differences in inequality. But how do apparently small differences in inequality get to us?
The amount of income inequality in society tells us about the scale of social class differentiation, of social distances and the scale of downward social prejudice and discrimination.
As the income differences between rich and poor increase, so status and status competition become more important. The bigger the differences between classes, the less social mobility there seems to be.
Comparisons suggest that social mobility is greatest in the countries with the smallest income differences. Far from being the land of opportunity, the US turns out to be the land of least opportunity.
The effects of inequality are not simply the effects of having to make do with low income and poor material living standards. If that were so, all the problems which increase with inequality would become less common as the developed countries got richer.
But there is no tendency for the richest of the rich countries to have lower levels of violence, of teenage births, ill health, obesity or prison populations, or for trust and community life to strengthen.
What counts is where your income places you in the social hierarchy. Although inequality is itself a form of institutional violence, most physical violence is not the poor attacking the rich.
The most common trigger to violence is people – usually young men – feeling put down and disrespected. Sensitivity to status issues is greatest among people denied status – denied access to the jobs, housing, incomes, cars and education which are markers of status.
That is why violence is most common in the poorest areas. What is worst about having to make do with second rate goods is feeling that they mark you out as a second rate person.
The psychological pain of low social status – feeling looked down on, being regarded as inferior, in contrast to being valued and admired as a person of “quality” at the top of the social hierarchy.
Rather than health being influenced mainly by the direct effect of material circumstances, it looks as if the pain of low social status itself is a powerful source of stress.
This stress compromises the immune and cardiovascular systems – to say nothing of how it makes us want comfort foods, another drink or a smoke. The biological effects of chronic stress are slowly becoming understood.
And just as low social status is stressful, so friendship is protective. Good relationships and lots of friends reduce stress, make us less vulnerable to disease, and substantially reduce death rates.
Instead of worrying whether we are unattractive, boring, or whatever, friends make us feel valued and appreciated. Hence cohesive and egalitarian societies are healthy – in every sense.
With the decline of community these issues have become ever more important. Modern mass society has increased everyone’s worries about how they are seen and whether they are accepted.
A comparison of hundreds of studies measuring anxiety found that average anxiety levels among children and young people are now higher than they were among psychiatric patients in the 1950s.
Essential to any regenerated socialist movement is the creation of a sense of solidarity and acceptance, where people do not fear elitism and exclusion – whether intellectual, social or material.
Richard Wilkinson is professor of medical epidemiology at the University of Nottingham. He is the author of The Impact of Inequality: How to Make Sick Societies Healthier (Routledge 2005).