Do we really want to know what’s actually going on? In the world and in the past and in plant cells and in space and in the flat upstairs? I get that it’s always going to be impossible to be sure. All any of us has to go on is a load of nerve signals hastily compiled into a vaguely coherent impression by the grey sponge that seems to be the site of the key thing that makes each of us whoever each of us is. It’s an impression that can get skewed by fear, rage, self-interest, hunger, a bad back or by being, to a greater or lesser extent, mad.

Anyone who’s suffered from sciatica will tell you how disconcerting it is to feel a pain you’re convinced is emanating from your leg but which is in fact caused by an injury, located somewhere in the spine, to the nerve responsible for leg news. But it doesn’t feel like a faulty line – the nerve doesn’t crackle. It just feels like a sore leg. It is a totally convincing, rather undramatic, delusion and a salutary reminder that when we think we’re definitely looking at a table, that’s actually just the narrative our brain is imposing upon unsubstantiated data supplied by the optic nerve.

On top of that, loads of the data our ocular nerves are getting hold of these days comes via various screens which are themselves imperfectly connected to, and flawed reflections of, the things that are really happening. So I totally accept that no one actually knows anything and, for all practical purposes, there is no such thing as objective truth.

Essentially, the appearance of a famous landmark will be different according to who you are

But that doesn’t necessarily mean it’s not worth searching for – in the same way the ultimate unattainability of complete cleanliness doesn’t invalidate occasionally using the Hoover. For millennia it’s been a sort of given that humans are always, in various ways, trying to work out what’s up. And the results have been mixed. On the plus side, it’s provided a huge variety of cheese and celebrity gossip. In the minus column, there’s our expulsion from the Garden of Eden [citation needed] and nuclear weapons.

Then last week I suddenly felt like we might be giving up the struggle. I read two very different news reports, but both were about denying or warping reality. And neither involved Donald Trump.

The first was that Cambridge University lecture timetables are being labelled with “trigger warnings” about the plots of various literary works, including The Bacchae and Titus Andronicus. So English literature undergraduates are being protected from the knowledge of, among other things, what one of Shakespeare’s plays is about, in case it upsets them. Will budding physicists soon be allowed to shield themselves from the shocking understanding of what a black hole really is, or what will happen to the Earth when the sun explodes? They’re unsettling truths.

Illustration by David Foldvari.

The context of this story was concern over how universities are becoming bastions of these trigger warnings, as well as of “no-platforming” and “safe spaces”, rather than of freedom of speech. Jo Johnson, the universities minister, says he wants to do something about it, which is nice to hear but not as nice as it would be coming from a government that wasn’t record-breakingly inept.

Unfortunately, there are many people who instinctively feel they have the right to be protected from opinions that offend them or facts they find distressing. It’s going to be difficult to talk them out of that position as they’ve convinced themselves there’s something immoral about being disagreed with. They want to be able to curate their experience of the world to exclude elements they’d rather didn’t exist.

I know the feeling. On Twitter, if someone sends me a message that, in retrospect, I’d rather I hadn’t read, I immediately “mute” them. This means I won’t see any other messages they send me but, unlike if I’d “blocked” them, they don’t realise I’ve cut them out and so don’t have something else to get cross about. So two truths are suppressed: I remain ignorant of what they’re saying and they don’t realise they’re shouting into the wilderness. I’m not proud of it, but it’s more relaxing this way. And, in my defence, I’m not a globally renowned seat of learning and they’re not Germaine Greer.

The second was the very different story that the new electric hoarding at Piccadilly Circus is going to have targeted advertising. There are hidden cameras within it that can apparently identify the age of passers-by or what make of car they’re driving and will change the sign’s marketing messages accordingly. This has been happening online for some time, but now it’s moving off the computer screen on to a tennis court-sized expanse of iconic central London wall. The wall will also offer localised wifi with which people will be encouraged to interact so their experience of that part of town can be further personalised.

Essentially, then, the appearance of a famous landmark will be different according to who you are. There will be no “true” version. The writing on the wall will be different for you than it is for someone else. Reality will be warped by subjectivity before it even hits the optic nerve. First the internet and now Piccadilly have become like a high-functioning sociopath, shape-shifting according to their short-term needs from whomever happens to be looking.

As it is, we spend too much of our lives in little pockets of the internet, surrounded by the slogans of products we’ve already bought and beliefs we already hold. Other online pockets seem strange and barbarian with their abhorrent views and crappy marketing. We can dismiss those people’s opinions, and they can dismiss ours, because, we think, those who disagree with us are simply “biased”. Their heretical viewpoints are the products of blinkered self-interest. Their way of looking at the world is wrong.

But at least we’re all looking at the same world. For now. More or less. We can agree on the theoretical existence somewhere of a definitive truth. Are we still up for seeking that truth or are we happy to compound our own subjectivity by being ever more protected from views we oppose and only exposed to advertising designed exclusively for our particular tribe?

It’s ironic that the advent of a technology facilitating unprecedented communication and understanding of the paradoxes and complexity of global events, and of billions of people’s reactions to them, is causing us to retreat from such knowledge. The apple’s tasting funny and we long for the peace of the garden.