The Earl of Beaconsfield, better known as Benjamin Disraeli, was a remarkable individual. A talented and successful novelist, he was the progenitor of one-nation Conservativism – and twice served as Prime Minister, combating Gladstone.

He is also remembered for the blunt advice which he handed out to a truculent colleague. “Damn your principles. Stick to your party.”

One or two Nationalists may be muttering similar sentiments at the end of a week which saw a scion of the Ewing dynasty suspended from the SNP’s Holyrood group for a week.

This decidedly mild punishment was imposed upon Fergus Ewing because he voted against Green Minister Lorna Slater in response to a Conservative motion of no confidence back in June.

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Mr Ewing is far from cowed. He says that, if necessary, he will continue to vote with his conscience and his constituency.

This, of course, sums up a classic political conundrum. Do elected politicians exercise a direct, personal mandate – or are they principally representing the party ticket which supported their elevation? There is a touch of both in there. And, of course, it must be right to reflect conscience votes. But turn the question around.

What do people think they are getting when they vote for a candidate representing a particular party? Do they only consider the expressed views of the individual? Or are they voting for an overall party programme and for a party leader intent on governmental power?

It is the latter, is it not?

Experience suggests that the personal vote for individual candidates, even notable ones, is decidedly limited. Folk are voting for a party and a leader. They express that vote through a candidate – whose personal character will, additionally, sway that decision either way.

That is true for constituency representatives, like Mr Ewing. It is even more the case for the 56 list MSPs whose presence at Holyrood is determined entirely by a party preference vote. (As always, Margo MacDonald was the exception. She won a list seat as an individual, entering her campaign launch event to the strains of “Only the Lonely”.)

Now, that does not – repeat not – mean that we are choosing automatons. Our tribunes should advance their own perspectives within their party group and in Parliament. They should argue and cajole.

In Cabinet, Fergus Ewing advanced centrist pro-growth policies. Biting his tongue, as he says, if he lost. He is no longer prepared to compromise. Speak to SNP folk at Holyrood and you will discern a certain amount of exasperation with Mr Ewing. Why, they ask, did he need to bring a top lawyer to the group meeting, supposedly a private discussion among political friends?

Equally, Mr Ewing has a fair degree of support within the SNP. Some of that comes from those who respect his decades of endeavour for nationalism – and cherish the memory of his mother, Winnie Ewing.

Some of it comes from people who support his economic perspective – and, in particular, distrust the Greens whom he has caricatured as “wine bar revolutionaries”.

And, frankly, some of the support for Mr Ewing arises from those who are otherwise disaffected and are content to see the SNP leadership under pressure. It would not be easy to corral such a disparate group into a coherent internal opposition. In any case, that is not Mr Ewing’s declared intention.

He is adamant that he wishes no ill whatsoever to the cause of nationalism. However, he presents a trenchant and persistent challenge to Humza Yousaf.

Only this week, Mr Ewing pursued the promise to upgrade the A96 trunk road. The FM sounded hesitant and uncertain in reply, aware that his Green partners dislike such projects. Challenges – and rebuttals.

Fergus Ewing says he was “literally born into the SNP”. True – and prompting respect. But not germane to a dispute over discipline.

Mr Ewing argues that the SNP he joined would never have provoked a choice between loyalty to party and constituency. Not sure that is entirely accurate – and I have covered the SNP since the 1970s.

In any case, the old SNP was a party of entrenched opposition. Now, they are in government – and more is expected. His vote against Ms Slater reflected disdain for her handling of the deposit return scheme – but also wider disquiet with Green policy.

Mr Ewing was, he says, standing up for his country and constituency. Leadership reply? The pact with the Greens was endorsed by the SNP. It covers confidence: that is, addressing the sort of challenge which confronted John Swinney in the previous Parliament; and supply, that is securing the budget. It works, they say.

However, there are two other issues. Uncertainty and frustration. Firstly, economic uncertainty. Do we address deprivation by higher taxes and fiscal distribution? Or by stimulating growth and so alleviating poverty at source?

Mr Ewing firmly advocates a stimulus policy – while the Greens disdain GDP growth as a target. More generally, folk are worried about the cost of living – and do not see governments, either in Westminster or Holyrood, offering enough in the way of solutions.

As they prepare for the Scottish Budget in December, the SNP are honourably riven over which course to pursue. Higher tax or stimulated growth. Would tax be too harsh? Would growth be too slow?

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My second issue? The other emotion currently assailing the SNP. Frustration. It is shared by the leadership – and by discontented party stalwarts such as Fergus Ewing.

Put simply, they cannot presently find a way to advance the cause of independence. It is just not featuring sufficiently for them in the contemporary political discourse, despite their continuing efforts.

Voters, including in Rutherglen and Hamilton West, want to hear remedies for their very present woes. Not perhaps, for now, that longer-term scenario for Scotland – although, to be clear, many remain potentially open to that cause, should a revived way be found to advance it.

Fergus Ewing reminds us, accurately, that the SNP was “never an ordinary political party”. It was, he said, one which put Scotland first. Quite so. And that broad aim may still coalesce those who would otherwise bicker.

But, right now, that very different party, the SNP, is facing very familiar political problems.