It's been a hell of a year. Not only has iconoclastic artist Ayanda Mbuli been shot to death for painting rude pictures and Malia Obama enrolled at a Limpopo university, but Julius Malema has vowed to kill gay people and Jacob Zuma has revealed that he has a powerful sexual appetite for young women caused by a medical condition.None of it was true, of course, but that didn't seem to matter to the thousands of South Africans who shared those stories online.Journalists are warning that we have entered the "post-fact" era, and, tired of being left behind global trends, South Africans seem determined to be in the vanguard of the new wave of completely fabricated news.I must admit that I'm slightly hesitant to announce the end of the factual era, mainly because I'm not sure it ever started. I like an empirical measurement now and then, and it's pretty important that we know when to plant crops and how to ward off gangrene. But you've got to admit that the history of our species is one long, glorious fiction, punctuated with a few alarming discoveries.Once you've made it past the fact of your birth, and figured out how to co-exist with the fact of being a social animal, you're likely to encounter only one more fact: death. The rest is an almost miraculous negotiated fantasy.For example, let's consider an idealised newspaper, printed early one Sunday morning in the golden era of "factual", pre-internet, pre-Trump reporting.Casting your eyes over a mass of tiny black marks on a white page - each of which has been agreed to represent a certain sound, which itself has been agreed to convey a certain agreed-upon meaning, you encounter reports about national news.This "nation", is, of course, an invention - a large group of people corralled inside an imaginary line called "the border" - while "news" is carefully curated fiction, selected for its power to keep certain fictions spinning along.Turning the page, you reach the financial section, discussing an invented store of value, a trading tool called "money".Finally, sport: an odd pastime in which arbitrary physical jerks are reinterpreted as hopeful or exciting or consoling fictions.Once you've digested this set of "facts", you go back to your day: living in denial about how much imaginary value-store you have left in the non-existent vault you call a "bank account"; believing that your invented deity is more powerful than other invented deities; being suspicious of people from outside the imaginary border because their agreed-upon daydreams are different to yours and they might force you to replace yours with theirs ...Of course, this approach is fertile soil for barbarism. If human rights are invented fantasies (and they are), then who is to say that they are more important than a despot's desire to slaughter his enemies? If politics are a fiction (and they are) why should Donald Trump's version of reality be any less acceptable than that of Bernie Sanders?Well, I'm not a philosopher so I don't have a concise or logically sound answer to those questions, but I do suspect that if we're going to get anywhere in this collective dream of ours, we need to try to pin down a few basic assumptions.One of these might be that some events are more harmful to us than others. For example, I have a sense that genocide is generally worse for everyone than peace, and that insular, bigoted, reactionary politics are generally more harmful to the forward-movement of a country than a more liberal approach.In short, some fantasies need to be given more weight than others, and some "facts" need to be held dearer than others.Proper journalists - trained to get as close to our agreed-upon truth as possible, with a sharp eye for manipulative waffle - are the keepers of that faith. And at the moment they're in trouble. And yet, wasn't that inevitable?Our shared beliefs might be almost universal but they're also shockingly fragile. An international border is a complex legal, political and military construct, but all it takes to obliterate it is a single step.Likewise, ideas of fair play, tolerance and human solidarity are entirely helpless against some charismatic git shouting: "It ain't so!" At the moment we all agree that the sun rises in the east, but east and west are fictions. If enough people repeated it on Facebook, trust me: the sun would start rising in the west.So what's the solution? I'm not entirely sure, but for me a useful start is to figure out which fictions are the least harmful to me and to the people I live alongside.And perhaps it's also worth remembering that marks on a page are just marks on a page. What they represent, well, you'd be surprised by how much of that is up to you...