CONSIDER rare things. The white rhino, platinum, a parking space in Edinburgh. And, of course, a prolonged discourse over Scottish tax.

Mostly, such rash talk is subsumed within a broader discussion about tax powers and independence.

About the scope of Holyrood’s fiscal clout, not about current tax policy.

This week, though, proved an exception with the First Minister facing close questions from Liz Smith of the Conservatives on the economic impact of tax differentials between Scotland and England.

More to come next week when the Scottish Government unveils a revised Medium Term Financial Strategy which is likely to set out tough options, including on tax.

This week’s exchanges followed Tory claims that most people in Scotland now face higher income tax than south of the Border.

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That assertion is based on calculations of a rising median wage – with Scottish tax bands failing to keep pace.

That is disputed by Scottish Ministers who say 52 per cent of Scottish taxpayers currently pay “slightly less”. They take pride in “the fairest and most progressive tax system in the UK.”

But what about the direction of travel? Humza Yousaf has hinted at the prospect of higher taxation in an effort to counter poverty.

Business is nervous. They welcomed the new forum meeting with Ministers this week, designed to reset a fractious relationship. The promise is closer – and earlier – consultation.

But Liz Cameron of the Scottish Chambers of Commerce said urgent action was needed now “to grow the economy by correcting policies that limit growth and investment.”

Hence those Tory questions. I was intrigued by two elements. Firstly, Humza Yousaf took considerable care to project a balanced perspective: action to tackle poverty but with “robust analysis” of fiscal policies to avoid “conflict with growing the economy.”

The FM cited stats countering claims that people might leave Scotland to avoid higher taxation.

Which generated my second point of interest. Ivan McKee intervened to offer substantial support, arguing that tax revenues could be increased by enticing working age people to settle in Scotland.

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Why intriguing? He is, after all, an SNP backbencher. Yes, but he backed Kate Forbes in the leadership campaign – and he left government, voicing regret at a lack of opportunity to foster enterprise.

This week’s intervention was, I am told, unprompted. It could signal a rapprochement – not that there was ever much of a rift. Mr McKee, an entrepreneur himself and Herald columnist, is well regarded in business circles.

Which brings me back to that Financial Strategy. On public spending, Ministers have already signalled change. There may be more targeting – rather than universal provision. And some budget lines may close altogether.

But the scope for cutting spending is limited, not least by consumer resistance, fostered by past promises.

So there will still be a considerable requirement for more revenue.

That could come from Barnett consequentials, particularly if UK Ministers feel they need to hike spending in England ahead of next year’s general election.

It could come from economic growth. Ministers are closely focused on that prospectus.

Or it could come from tax. Maybe new taxes? A wealth tax, as backed by the Greens?

New taxation is not ruled out but I do not discern much Ministerial enthusiasm for it, not least because it would require Treasury sign off. And the Treasury tends to say no.

Which could mean raising more cash from existing powers. In short, income tax. Still not definite – and not by much. Remember that counter-balancing aim of boosting growth.

If tax does increase in Scotland, it will be a hard sell for Humza Yousaf, especially if the Tory forecast comes to pass and the majority in Scotland end up paying more than south of the Border.

He has three basic responses. Firstly, he advocates the principle of progressive taxation, aimed at combating poverty; the objective he espoused in the leadership campaign.

Secondly, he can summon the familiar social contract argument by pointing to the advantages enjoyed by taxpayers in Scotland – such as free prescriptions, free higher education and child payment support.

The costly advantages which, in themselves, limit the scope for spending constraint.

And the third? He can rebuff the Scots Tories by noting once more that they initially backed the Truss/Kwarteng tax cuts for higher earners – and wanted them replicated in Scotland.

However, that one is decidedly a declining asset. Not sure it endures.

Still, it is at least welcome to have something approaching a fiscal fight in Scotland. It brings a new dimension to a distinctive battle which is shaping up south of the Border.

Not spotted that? Consider comments this week from the Home Secretary Suella Braverman and from Nigel Farage, a prominent promoter of Brexit.

Ms Braverman told a US-backed conservative conference that we should curb immigration by, among other things, training our own fruit pickers.

It caught my eye not least because, as a callow youth, I occasionally spent a day contentedly picking berries in the sun near my home in Dundee. As I recall, the training was limited.

However, the Home Secretary, as you will have guessed, was not really talking about fruit. Instead, she was nurturing a few ripe political rasps to chuck at the Prime Minister.

Ditto Nigel Farage with his claim on the telly that Brexit has failed. Look a little more closely. He is very far from saying that he was wrong in advocating withdrawal from the EU.

Instead, he is arguing that the current Tory administration has failed to follow up Brexit with sufficient free market liberalism in the UK.

Both these contributions, then, are part of a calculated campaign by the political Right to regain the initiative which they believe they lost when Rishi Sunak replaced Liz Truss in Downing Street.

It is not really about contemporary economic policy – but about the political contest which will follow when the Tories win or, more probably, lose the next UK general election.

Another stat caught my eye this week. There was a 1.4 per cent rise in the number of Scots who are “economically inactive”.

We need to respond with an intellectually active – and politically diverse – discourse of our own. This week was a modest but welcome beginning.