Neil Oliver has lost it, totally lost it. Over the last two years or so the former TV historian has buried himself deeper and deeper in to a rabbit hole of conspiracy theories.

Worse, he is trying to pull the rest of us down after him. Every week Mr Oliver delivers a trademark monologue on GB News, by far Britain’s most irresponsible TV station.

Early this year, his eyes fixed on the camera, the self-styled “Coast Guy” claimed a “silent war” was being waged by generation after generation of politicians to take “total control of the people” and impose a “one-world government”.

This was bonkers. It also bone-chillingly echoed some of the most poisonous anti-semitic mythologies of modern times.

Searchlight, the anti-fascist magazine, compared Mr Oliver’s language to that of a particular 1980s conspiracy theory featuring – in a classic trope – the Jewish Rothschild family.

Cue real concern from serious people. After Mr Oliver’s broadcast both the Board of Deputies of British Jews and the all-party group on anti-semitism at Westminster urged GB News not to indulge conspiracy theories.

The TV company – it should be added – responded to criticism by saying it abhored “racism and hate in all its forms and would never allow it on the channel”. M’okay.

Mr Oliver - who, let us be clear, did not mention Jews in his tirade - responded with another rant, this time about those who use labels like ‘anti-semite’ to shut down debate. He bemoaned “the slow creep of ugliness in to public discourse”. See, like I said: he has lost it.

His February GB News segment on “world government” – I think – remains a remarkable episode, a stunning low, in the history of British television. But it was not an isolated incident.

Last month Mr Oliver retweeted an unambiguously anti-semitic cartoon focused on Bill Gates, the tech billionaire and vaccine champion. Some media commentators assumed this would end his career. It did not.

Mr Oliver has been raging against public health measures for a couple of years now. Just before his GB News gig he told this newspaper that Covid lockdowns were "the biggest mistake in world history”.

Strewth, that was crazy talk. Since he has railed against vaccines. Presumably his editors are OK with such nonsense. They should not be.

There are plenty of people who are cynical about journalism, and they are not always wrong. But our trade - at its very heart - has a simple principle: what we publish or broadcast should be compatible with objective reality.

World Government conspiracy theories, as if this needs to be said, cannot be.

That means Mr Oliver - and other deeply unserious contributors to GB News - remain a big headache for the UK’s broadcast media watchdog.

Ofcom is going to have to figure out where to draw the line between free speech and fair comment and dangerous misinformation. I do not envy them their task, but it is a crucial one.

Some commentators have started pushing against the very idea of ‘misinformation’. It is if they see reality as a prison and facts as shackles.

Mr Oliver’s conspiracism is not just a problem for media regulators. It also presents a reputational risk for Scottish academic institutions. The TV presenter has honorary doctorates, including from Glasgow University.

More importantly, in 2020 Mr Oliver was elected a fellow of the Royal Society of Edinburgh, Scotland’s national academy of science and letters.

That was some honour. It should now, if at all possible, be cancelled.

The RSE, like this newspaper, was created in 1783, as our country emerged as one of the engine rooms of the Enlightenment.

The organisation is not a dusty relic. It is our paramount think tank, bringing together 1,800 or so intellectuals from a high variety of disciplines and backgrounds. Its aim, now as back in the 18th century, is to spread knowledge, not least in to public policy.

This noble objective needs communications skills as well as big brains. Which is why Mr Oliver was made a fellow. The TV presenter’s discipline is officially listed by the RSE as “public engagement” and “understanding”.

I can see why fellows would have wanted Mr Oliver in their ranks. He had an easy manner in front of camera, a journalistic knack for turning complex history stories in to TV soundbites.

Sure, Mr Oliver, until recently a fairly insipid unionist, irked very online Scottish nationalists. And, yeah, some hardcore academic historians – usually privately – scoffed at their TV peer.

But none of that will have worried the RSE fellows who elected Mr Oliver. They will not have cared about his then banal politics, and they will have known the value of popular broadcasting on nuanced issues.

But here is the rub: Mr Oliver’s value to RSE in 2020 was his ability to pass on knowledge. He is a problem for the body in 2023 because he instead spreads ignorance.

The good news is that Mr Oliver is not actively involved in Society business. He does not seem to trade on his fellowship.

However, as RSE fellows championed evidence-based, life-saving responses to Covid, Mr Oliver – who has no relevant expertise – was on air undermining them. That looked bad.

I say all of this out of deep personal respect for the RSE. But, sorry, the body has given Mr Oliver a globally recognised intellectual kitemark he no longer deserves.

I think Coast Guy is waging a TV war against the very principles of the Age of Reason our national academy was founded to uphold.

Someone should take a stand, make a formal complaint. That will not be easy. Nor would be the disciplinary process that would follow.

The RSE, like TV regulators, may find itself wrestling with the boundaries of free speech, with the challenges of misinformation.

But I cannot imagine any Scottish body better placed to think through such issues.