In front of around 500 people, Jeremy Corbyn strode on to the stage to the sound of about six hands clapping. "Thank you so much for that warm reception," he said. The reception had not been warm at all, but these were the words he had already decided to say, and so say them he did. It was, in its way, a beautifully clear window into the Corbyn psyche, which is best understood as that of a wasp.
When a dying wasp flies to the top of a window for the 100th time, then stumbles to the bottom and tries again, it is not because it is stupid, as such, it is because it is biologically incapable of learning. It is born and it will die with all the cognitive function it will ever have. It is, quite literally, stubborn by nature.
Jeremy Corbyn has opinions that were bequeathed to him 40 years ago by Tony Benn. The software can no longer be updated. There are whole areas of cognitive function that he simply does not have access to, and chief among them is the idea that he could ever, possibly, be in the wrong.
Because Jeremy Corbyn is a socialist, and Jeremy Corbyn is on the side of the little guy against the big guy, there can, on Planet Corbyn, exist no scenario in which Jeremy Corbyn is the bad guy.
Which is why he can turn up to a manufacturing conference, and mumble his way through a boilerplate speech, and not feel it necessary to address with any more than 10 words the fact that seven of his MPs, some of them among the most respected in his party, walked out. He has since lost another. They did so claiming he had made the Labour Party not merely unfit for government but also institutionally racist, and beset with a culture of bullying and intimidation.
Asked about this at the end, not once but twice, he could only offer the following words: "I hope they realise they were elected to parliament on a manifesto that was based around investment in the future; that was based around a more equal and fairer society; that was based around social justice - and it is that programme that we are going to put to the electorate in the future, that does have enormous support. They were elected to carry out those policies. They decided to go somewhere else."
It's never me, in other words. It's always you.
There are, we are led to believe, more resignations to come, for which Corbyn will also not be to blame, at all. These words come as John McDonnell says Labour must launch "a mammoth listening exercise".
If it is to do so, it will have to do something about the fact its leader is as deaf as a post.
One of his now former colleagues, Luciana Berger, served in his shadow cabinet at first. Now she's been bullied out of the party by racists, and here was her leader, impervious as ever to the idea that any of the blame should land on him.
His deputy leader, Tom Watson, said yesterday: "I love this party, but sometimes I don't recognise it."
It's a wonder, really. It's been almost three and a half years now since Jeremy Corbyn was elected its leader, in this very same room, as it happens. It is entirely recognisable now, as Corbyn's Labour Party. Its transformation is complete.
It is the party in which Jeremy Corbyn is always right, and all who disagree must yield before him.
A long passage of his speech, by the way, was on the subject of lifelong adult learning. It's a subject he evidently feels passionate about.
"It makes no sense for people to only be educated for the first quarter of their life and then work for the rest of their days with outdated or insufficient qualifications," he said.
It's an interesting observation, especially when placed next to something he said within a few weeks of becoming Labour Party leader in 2015.
"Because I've never had any higher education of any sort, I've never held in awe those who have had," he said then. "Some of the wisest people you meet are sweeping our streets."
It is one of the most stubborn things I can ever recall any politician, or indeed any person, saying.
Jeremy Corbyn had an immensely privileged upbringing, and excellent schooling, from which he emerged with meagre qualifications.
His response has been to deploy his own inadequacies to reduce others to his level. To rebadge his failings as some kind of kinship with those who have faced obstacles he has not. If he is such a believer in lifelong learning, he'd better get cracking.
He has got his eye on a job he is hopelessly unqualified for, and, as things stand, he is far too arrogant to consider that he might need to do something about it. (© Independent News Service)