Everyone’s saying it, so it must be true. We live in a post-truth era, in which unsubstantiated statements are swallowed whole. The less palatable they are, the more easily they slip down.

Post-truth was made word of the year – the Oxford Dictionaries’ International Word of the Year, no less. Post-truth is of course instead of truth, not after it as in, say, post mortem or post-Apocalyptic.

As you see, even the term post-truth is lying through its teeth. But what does it matter?

Post-truth got some massive boosts this year with Brexit and the US Presidential Election. While Michael Gove didn’t actually start it, he did famously say that people in this country had “had enough of experts”.

Experts are now superfluous and fact-checkers obsolete. These days momentous decisions are made without anyone bothering with evidence.

That doesn’t just make me worried. It makes me deeply suspicious not just of politicians but of pretty much everything, cute animal videos included. What if I’m not watching an Alsatian licking a kitten clean, but just a cleverly doctored video of a dog preparing his lunch?

I can see how we got to post-truth. Everyone has an opinion, and now it has just as much value as anyone else’s. Social media provide an echo chamber where anyone can have their say, as well as share hatred and intolerance.

Twitter wasn’t big in Lao Tzu’s day, but I think he nailed it with “Those who know do not speak. Those who speak do not know.” 

As a doctor, I’ve lived with post-truth beliefs for some time. One patient with appendicitis, who, on being advised surgery was needed, declared that it wasn’t for him. An operation might be our way of doing things, but not his. Thus he belted out of Accident & Emergency into the night. Saddest of all in my view is the mother who, after lengthy discussions, still refused immunizations for her baby. “I’m doing what I think is right,” she told me. “After all, that’s the most important thing.”

The most important thing? God help her child.

It’s clear how we got to the age of unreason, but it’s less clear how we’ll climb out of it. Trump’s inauguration is scheduled for next Friday, and we are where we are.  Though there is a well-known story about a tourist in Ireland. Lost, he asks one of the locals for directions to Balbriggan. The Irishman replies “Well, sor. If I were you, I wouldn’t start from here.”