APART from my colleagues on The National, the columnist I admire most is Matthew Parris in the Times of London. His piece on Saturday ran under the heading “May has my vote but only with gritted teeth”. I liked that line because it neatly summed up my own feeling about Nicola Sturgeon.

My column in this spot last week appeared on the day the SNP’s election manifesto was to be launched, so it had to be written the day before. When I got down to work I could not know exactly what was going to be proposed, but enough had been leaked for me to be fairly sure I would dislike a lot of it. So things turned out.

I still underestimated quite how much I was going to dislike it, even though it contained a lot of predictable items. It supported two tax rises. It wanted to reverse two tax cuts. It supported two kinds of higher tax allowance, one cap, one freeze and a regulator of price hikes, as well as the closure of loopholes in the taxation of sugary drinks.

It called for cash freezes on benefits to be abolished, and for the work allowance of all benefit claimants to be reinstated, along with the reversal of cuts to bereavement payments and widowed parents’ allowance. On a couple of the hottest topics in the election campaign so far, it wanted the rape clause and the bedroom tax to be done away with.

In terms of getting and spending, it had much more about spending than about getting the money to be spent. Yet our economy extends well beyond the welfare system. This system could not exist without the private sector in industry and services that earns the incomes to be taxed for it. But the only major proposal for the private sector was an increased investment allowance for companies. For that one incentive to growth and expansion, there were dozens of proposals either for higher benefits or for stricter commercial regulation. It would have been nice to see just a bit more balance. Altogether, the manifesto’s aim was clear: austerity in the UK should be brought to an end with £118 billion of extra spending.

It is not that I disagree with all of this, but I wonder if chucking money at the welfare state is really the way to solve all its multiplying problems. As the manifesto itself showed, we are dealing with a structure so enormously complex and unwieldy that its own bureaucrats can scarcely understand it, let alone the poor and deserving who are supposed to be its beneficiaries.

It is open to special pleading from every quarter, and at the same time available as a pork-barrel to any political party ready to exploit it, the SNP being a fine example. Enormous sums are squandered, yet daunting social problems persist – which is why the most progressive societies have started looking for something else. Myself, I favour the Universal Basic Income, as now being run or planned in Finland, Alaska, Ontario and Namibia.

It is more efficient overall, it makes many poverty-stricken families better off and it does not humiliate them. But in Scotland the biggest problem is usually just to get anybody to look at a new idea.

A more damning criticism still of the SNP manifesto is that has virtually nothing to say on how its demands are to be paid for. Even the Labour party attempted comprehensive costings of its own wish-list, spurious as they are. But for the SNP all the necessary money is somehow just going to be there, and we punters should not bother our silly little heads about where it will come from. In the last resort the English will be bound to pay: they owe us £200 billion for 40 years of oil production anyway, and the latest figures show they are still coughing up for us even though the revenues from the North Sea have now run out. That is the price for their precious Union, and we will just keep sending them the bills.

But hang on a second. This election is supposed to be in part about independence. A free Scotland would by definition get no more money out of London. In that case, it would also be at the moment in a serious situation, because our economy is about to slide into recession. This cannot be blamed on UK policies, for the UK economy continues along a path of modest expansion which is enough to keep the wolf from the door (though the wolf continues to lurk outside in the forest of Brexit).

This particular crisis may be temporary, but the long-term trends are not at all comforting. In the last full year of 2016, the Scottish economy grew by 0.5 per cent compared to two per cent in the UK as a whole. I would have thought this might have been worth a mention in the SNP’s manifesto, if only as a prelude to saying what was to be done about it or to complaining that in the present state of the devolution deal we have not the fiscal instruments to deal with it.

Our Finance Secretary, Derek Mackay, puts it all down to the steep fall in the production and price of North Sea oil and gas. I am not myself sure this is the complete story, but if it is then it raises a more important question. Since North Sea oil and gas are not any time soon likely to come back onstream in the same abundance as before, do we face a permanent, or at least durable, situation in which the rate of growth in the Scottish economy runs at just one-quarter of the rate of growth in the UK economy?

In that case, we are in for big, big trouble. With such a miserable comparative rate of growth, by definition we are going to become steadily poorer than England. We will have trouble in financing our welfare even at the present levels, let alone any higher level. When it comes to a second referendum, our enemies will point this out: “Vote independence, vote poverty”, they will say. What is our answer going to be?

I apologise for raising these awkward points so close to a General Election, but I have always said, ever since I started writing this column, that economic growth has to be our absolute priority. No other objective can compare with it, because without it Scots simply will not in a majority opt for independence. I see little sign of that point sinking into the collective mind of the Scottish Government, but perhaps from Friday it will see a rethink as necessary.

In such circumstances, why vote SNP? Because it is the only chance of a change for the better. The Tories who are the main rivals will worsen the situation of the Scottish economy. They will blunder through Brexit. They will halt, or try to halt, the immigration that we in Scotland need for growth. When the economy slows in the next couple of years they will turn to fatuous policies such as the creation of housing bubbles that are irrelevant to us. As for the Labour party, just don’t get me started. And of the LibDems I say: who?

So there we have it: for all its faults (and they are legion), the SNP is the only rational choice that the economic Scotsman or Scotswoman can make on Thursday.