It is generally agreed that economic inequality (however defined, and measured) is bad for social cohesion, and bad for economic growth.
The corrosive effect on social cohesion seems self-evident. That would also seem to suggest a potential problem for democracy, as economic disposession leads to the rise of political extremism (and potentially an imminent disastrous British exit from the European Community).
The problem for economic growth is that if all the nation’s capital is in the hands of an oligarchy, then there will be a shortage of disposable income for the consumption of anything except luxury goods (and not that many of those). Without retail spending, and house purchase, the UK economy will tend to stall.
(This growth based on unsustainable spending is far from ideal, but at present that seems to be the reality. Others have argued for prioritising economic stability over growth.
Several OECD reports warn about the damage to social cohesion and economic growth.
May 2015“In It Together: Why less Inequality Benefits All”
A 2011 study “Divided we Stand: Why Inequality Keeps Rising” by the Organisation for Economic Co-operation and Development (OECD).
In the UK the Office for National Statistics has a statistical theme of household income inequality, which at least suggests some concern about this issue in central government
Prominent individual sociologists have also expressed concern. Professor Danny Dorling of Oxford University is an example:
As have a number of prominent economists:
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