Research showing that the bottom 10 per cent of the population has seen its income fall by 17 per cent while the top tenth has seen a 62 per cent rise has been supplemented by new data on spending and mobility.
When spending is examined, far from falling, that of the bottom 10 per cent has risen, by around 14 per cent. And those who make up the bottom 10 per cent are not a static, poverty-ridden underclass, but a much more mobile group than many once thought - with between a quarter and a half moving out of the bottom 10 per cent each year to be replaced by others falling down the income ladder.
The world is more complex than once it seemed - and the evidence that the poor have got absolutely poorer since 1979 is decidedly suspect.
The latest figures are the first good news the Tories have had on the subject in a decade, and Peter Lilley, the Secretary of State for Social Security, was using them yesterday.
But as with all figures, there are problems. For a start, a tenth of the population is a huge number - 5.7 million people. Buried within them are almost certainly people who have got stuck. And the data from which all the figures come, household surveys, exclude those at the very bottom of the pile - the homeless on the streets, those in hostels and bed and breakfast. Their numbers are not large. But there are undoubtedly many more of them than 20 years ago and they are the visible evidence of a more unequal society.
This is the core of the argument. For whether or not the bottom 10 per cent have got absolutely poorer since the mid-1970s - the widening gap in income distribution started before Margaret Thatcher came to power - it is clear they are relatively poorer, compared both to the middle and the top.
For them, paradise has been denied. Even using the spending figures - which show a less sharp growth in inequality than the income figures - those at the top have done three times better than those at the bottom, and been able to save an awful lot more to boot. And while widening inequalities have been a feature of most developed societies in recent years, what evidence there is suggests that inequalities have widened faster in the UK than in most other countries.
At some point, this is likely to matter to any society that wants to maintain its cohesion. A section at the bottom that sees itself becoming increasingly detached is unlikely to have much sympathy for the top. And a top end of society increasingly able to make its own provision for education, health and income and care in old age may well become less willing to pay the taxes to help those at the bottom - either into work or for life where work is not possible. It hardly sounds like a recipe for peace.
The challenge Peter Lilley laid down yesterday to those who believe society is too unequal was to state what level of inequality they would accept - and why. But it begs exactly the same counter-question to those who believe the recent acceleration in inequality not only does not matter but has been a positive good because it has provided greater rewards to those who have succeeded. What final level of inequality are they prepared to accept, and why? And do they believe the current trend is sustainable?
The challenge is a real one for both parties. It is unlikely that under the next government a trend that began before the Conservatives took power will cease. It has been driven not just by domestic policies on taxation, employment and benefits but by global forces which include trade and technology.
To halt the trend towards greater inequality at the bottom, let alone reduce it, is likely to require higher spending - on in-work benefits, on education and on training as well as on benefits for those who cannot work. Dramatic economic growth aside, that means either higher taxes or a more selective welfare state in pensions, education and health to release the cash another way: a route which would further detach the have-a-lots from the have-nots, while hitting those in the middle who are just too well off to qualify for tax-funded aid.
Neither provides an easy answer. But without one, the poor will not only always be with us but are likely to get relatively poorer.