As you know, I do love a good metaphor, but I’d never resort to anything as cliched as a sinking ship, or a train hitting the buffers, so let me tell you about my boiler. It’s been in place now for quite a long time, there are lots of things wrong with it, and it may need to be renewed. You get where I’m going with this, right?

The man who services the boiler, Alan – nice guy – was out to look at it the other day and discovered that a fuse had melted, another part had come loose, and the pump needed replacing. This is what happens to complicated systems as they age, he said; one bit goes wrong which causes another bit to fail and eventually the system is beyond repair. Whatever word you use –entropy, collapse, decay – it applies to pretty much any complicated man-made system in the end. Boilers. Computers. Cars. Governments.

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So, where are with the present government in Scotland? For a long time, it looked like a pretty efficient system; it was well-maintained and run, particularly the PR department. But increasingly some parts have decayed, some have had to be replaced, some of the fuses are prone to meltdown (Humza Yousaf), and it’s now getting to the point where the system itself is under considerable strain. Which is the end of all the boiler parallels. I promise.

Throughout it all, what has kept the government together, and maintained it long after other governments might have fallen, is the First Minister herself. She is a politician of prodigious ability and talent, and for a long time she appeared to be immune to the normal effect of time on popularity. Even now, given everything that’s happened in the last few weeks, her approval ratings remain relatively – some might say inexplicably – high.

But that said, I’ve been wondering about some of her recent statements and pronouncements and whether they betray an emerging issue, a deeper disorder, a problem that many, if not most, leaders become prone to in the end. It crossed my mind because I’ve been reading the updated edition of The Hubris Syndrome by David Owen, founder of the SDP, former Cabinet minister and doctor of neurology and psychiatry. The premise of his book is that political leaders, particularly ones that are in power for a while, are prone to a personality disorder that manifests itself as over-confidence and contempt for others. Owen calls it Hubris Syndrome.

Let’s look at some of the diagnostic features shall we, and you can judge for yourself. Hubris Syndrome, says Owen, is particularly associated with leaders who have experienced overwhelming success, which means it’s different from most other personality disorders. The syndrome isn’t something that develops in normal adults, it’s acquired by political success. It is a disorder of the possession of power and subsequent election victories appear to increase the chance of it developing, and getting worse.

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The list of suggested symptoms is interesting, and particularly telling in Sturgeon’s case. They include a strong or excessive self-confidence. A habit of conflating self with the nation or party. A contempt for people who disagree with you. And a tendency to believe that you are accountable only to a higher authority (in extreme cases, it could be God, but it can also be “history” or “the people”). There are other symptoms, but Owen suggests the presence of three or more of the defining characteristics can be indicative of the syndrome.

Now, I know this is where some readers will think I’ve gone too far – others may still not have recovered from the three paragraphs of boiler metaphors – but I think there is a prima facie case that the First Minister may be showing signs of the syndrome. The over-whelming self-confidence is certainly there, and there’s precious little evidence of some of the qualities which Owen says can protect against the disorder: humility, modesty, humour.

Some of what the First Minister, or her spokespeople, have said in recent days is also revealing. Ms Sturgeon said she would respect the work of the inquiries, and yet only the other day her spokesman suggested the Salmond committee was not a “serious” parliamentary committee and was guided by “base political motives”. I have to say that sounds to me like one of the symptoms: contempt for people who disagree with you. As for the suggestion that the committee suppressed evidence, I think anyone who watched the Government’s attempts to stop the committee seeing the papers it asked for will have a good laugh at that one.

We should also take a good look at some of the other symptoms of Hubris Syndrome: the tendency to appeal to a “higher authority” for example. After she gave evidence to the inquiry, the First Minister responded to criticism from the opposition by saying she would submit herself to the “ultimate scrutiny”: “the scrutiny and the verdict of the people of Scotland, the verdict that matters most”. This is something the First Minister and the SNP have been fond of doing in recent months: it’s a way of trying to link yourself to a greater sense of destiny and power. And the assumption that underlies it, that the verdict of the people will support the First Minister, is textbook hubris.

I think some of the First Minister’s other comments in recent days can also be seen as indicative of the disorder – that outburst about the “old boys’ club” and “Alex Salmond and his cronies” for example. And all those instances of “I don’t remember” or “I don’t recall” during her evidence to the inquiry may reveal another of the symptoms, which is a disregard for the details of government and policy-making. How else are we to interpret so much forgetfulness from the woman who runs the Government?

All of this is just a theory of course – and perhaps the answer is to limit how long someone can be First Minister in the way that the term of a US president is limited. I also accept that, even if Nicola Sturgeon really is demonstrating some of the symptoms of Hubris Syndrome, she is still very able in many other areas.

But look at what happens to people who’ve been in power for a long time. Look at Thatcher. Look at Blair. They get over-confident. They start to believe the praise. They start to despise those who disagree with them. They start, for want of a better phrase, to lose it. And when that happens, it usually – but not always – is the beginning of the end.

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