When Jordan Peterson and Slavoj Žižek met a fortnight ago in Toronto to do battle on the theme “Happiness: Capitalism v Marxism”, it cost US$14.95 (£11.60) to watch online, and touts were selling tickets for hundreds of dollars. Peterson, not having found time to read any of Žižek’s books, launched instead into an attack on The Communist Manifesto. In response, Žižek riffed about China, Trump, liberals, antisemitism and cheese. In the end, both men agreed that well-regulated capitalism was a good thing. It was billed as the “debate of the century”, and in a way it might as well have been: it was a perfect, if mostly harmless, illustration of why debate itself is such a bad idea.

We are told debate is the great engine of liberal democracy. In a free society, ideas should do battle in the public forum. Those who seek to lead us should debate with one another, and this will help us make the best possible informed judgments. Schoolchildren should be taught debating skills to better prepare them for the intellectual cut-and-thrust of the adult world. The rise in formal debating events such as those organised by Intelligence Squared enables citizens to better understand complex problems. People whose views we find abhorrent should not be ignored. We should debate with them, and so point out the flaws in the arguments. The more we debate, the happier and more civilised we will be.

That’s the theory, anyway. In practice, modern debate has a structural bias in favour of demagoguery and disinformation. It inherently favours liars. There is no cost to, and much potential advantage in, taking the low road and indulging in bullying and personal attack. There’s a reason why we talk about “point-scoring” in debates, and it is because we think of a debate as like a boxing match: it’s a competition rather than a collaboration. (If you can bear it, you can watch online a 2005 debate between Christopher Hitchens and George Galloway on the Iraq war: the result was that everyone lost.) In a recent Pew poll, just a quarter of Americans agreed that “the tone of debate among political leaders is respectful”. Many Britons who spend Thursday evenings hate-watching Question Time would agree.

Online, the call to 'debate' is made by men as a way of attacking women with whose opinions they disagree

Who cares, though, when non-respectful debate can be a money-making circus? Why not invite Steve Bannon, long-time fomenter of far-right anarcho-nationalism, to be “debated” at your literary event, as the New Yorker retreated from doing and the Economist still did? It’s all just grist to the entertainment mill, to the “marketplace of ideas”, isn’t it? But the demand for spoken “debate” in the first place is increasingly an outright aggression: it is the favoured weapon of fluent trolls who wish to be free of the accountability to evidence that comes with written argument.

Online, meanwhile, the call to “debate” is increasingly a gendered demand, made by men as a way of attacking women with whose opinions they disagree. “‘Debate me’ is a tactic of attrition,” says the writer and critic Sarah Ditum. “When some guy shows up in my email, or on Twitter, or in comments demanding ‘a debate’, he’s not after a back-and-forth argumentation closing in on a conclusion; he’s after throwing up enough dust that I ultimately decide stating my opinion is more trouble than it’s worth.”

The US author and journalist Leigh Alexander agrees. “For a certain kind of man,” she observes, “who is either too privileged or otherwise too sheltered to have engaged much with the meat of life, the field of debate is the only place he encounters issues. Because he has no skin in the game, everything is just a thought experiment. Right now the world is like: ‘Excuse me sir, would you please move over? Can you listen to what I’m saying? Can you stop touching me, can you stop hurting me, can you take no for an answer?’ And these guys, these children, go ‘Debate me, debate me, debate me.’ It’s pathetic.”

Such tactics are not limited to the online world. After newcomer Alexandria Ocasio-Cortez unexpectedly won her 2018 Democratic primary in New York, the “alt-right” TV pundit Ben Shapiro, formerly of Breitbart, offered her $10,000 to “debate” him. She responded tartly that such demands were the equivalent of catcalling: “I don’t owe a response to unsolicited requests from men with bad intentions.”

Last year’s Senate confirmation hearings for Brett Kavanaugh were deliberately engineered, meanwhile, to be effectively a “debate” rather than a sincere investigation. Republican senators refused to call other witnesses – in particular, Mark Judge – who might have corroborated Christine Blasey Ford’s version of events. Instead the hearings were reduced to a mere “she said, he said”, giving Republicans exactly what they needed: plausible incredulity.

Facebook Twitter Pinterest ‘I don’t owe a response to unsolicited requests from men with bad intentions’ … Alexandria Ocasio-Cortez . Photograph: Andrew Kelly/Reuters

Who really loves “debate”? Shills, bullies and those who want to muddy the waters on objective questions. Last year, the philosopher and Green party activist Rupert Read refused to appear on BBC Radio Cambridgeshire to “debate” global warming with a denier. Fundamentalist Christians who want creationism to be taught in American schools urge people to “teach the debate” about evolution, even though no such debate exists. The insistence that there should be a “debate” is very often a way of masking the truth by borrowing the presumptive virtue of the idea itself. We are a democracy; if you don’t want a debate you must be a fascist.

Spoken debate also favours liars, who know that even if their opponent attempts to rebut them, it will often be reported as “balance”. Perhaps the facts will be checked later, and the broadcaster will admit fault – as the BBC did after letting Nigel Lawson talk demonstrable rubbish about climate on the Today programme – but of course, by then, few of the original audience will be paying attention.

In 2009, George Monbiot refused the challenge of a live “debate” on anthropogenic global warming with the geologist Ian Plimer. “It takes 30 seconds to make a misleading scientific statement and 30 minutes to refute it,” Monbiot wrote. He suggested that he and Plimer first have a carefully sourced written exchange, but Plimer refused. They did eventually argue on television months later, but only because, Monbiot says now, the presenter Tony Jones understood climate change and was “highly resistant to bullshit”.

In recent years, especially for presidential debates in the US, teams of online fact-checkers have nobly attempted to police bullshitting in real time. But it doesn’t make any real difference, because the vast majority of the audience isn’t paying attention. During the first presidential debate in 2016, Hillary Clinton said: “Well, I hope the fact checkers are turning up the volume and really working hard” – a forlorn hope, not because they weren’t, but because only a tiny minority of the electorate cared either way. The whole series of debates was staggeringly futile anyway. Clinton evidently “won” them all, but it didn’t matter. All Donald Trump had to do, it turned out, was stand there and say: “No puppet, no puppet, you’re the puppet”, and he became president.

Since facts aren’t the real battleground, clever debaters will operate on a different level, for instance making dark insinuations that are designed to sow doubt in the audience’s mind. During the French presidential debates in 2017, Marine Le Pen said to Emmanuel Macron: “I hope that we don’t learn that you have an offshore account in the Bahamas.” There was no evidence that he did.

Facebook Twitter Pinterest Dark insinuations …Marine Le Pen and Emmanuel Macron prepare for a live TV debate, May 2017. Photograph: Chamussy/SIPA/Rex/Shutterstock

Dark arts aren’t a lamentable perversion of debate; they are the whole tradition of it. And people have been pointing this out ever since people have been debating. In Plato’s dialogue Gorgias, Socrates meets the titular character, who is a rhetorician, describing himself as someone “able to speak and to persuade the multitude”. This skill, Gorgias thinks, is the greatest of all arts. Socrates is sceptical. Debates (or “disputations”), he points out, “do not always terminate in mutual edification, or in the definition by either party of the subjects which they are discussing”; indeed, very often they turn into abusive shouting matches. Socrates argues that rhetoric is not an art, but an “ignoble” practice, a “counterfeit” of politics that favours the strongest speaker, and which tends inevitably to injustice.

Modern critics of the format add to such worries. In a 2016 paper, Critiquing Debate, the professor of communication James P Dimock points out that time limitations favour familiar cliches over surprising new ideas. Because a speaker in a formal debate must fit his or her claims into two or four minutes, it is easier to propose stereotyped arguments that sound like mainstream “common sense”, whereas a counterintuitive opinion would require more supporting detail, and so often more time than is actually available. “A debater need only suggest Iran has no right to arm itself with nuclear weapons,” Dimock notes, “but considerable resources would be required to support the contention that the United States has no right to their weapons.”

So the art of debating is one that rewards liars and bullies, is about beating the opponent rather than finding the truth, and is structurally biased in favour of conservative bromides rather than surprising new ideas. If that’s what debate is like, perhaps we shouldn’t aspire to be good at it. “Of course, it’s not just the demagogues whom spoken debate favours, but also the posh boys – I know, I’m one,” Monbiot says now. “When Jeremy Corbyn flounders at PMQs, part of me thinks: ‘For God’s sake man, just go for the throat.’ But another part of me thinks: ‘This whole tradition stinks, and it’s almost to your credit that you haven’t mastered it.’” In any case, most parliamentary debate is futile, because a majority government can impose the whip and do whatever it likes. Meanwhile, the recent Brexit debates leading up to the series of “indicative votes” signally failed to convince a majority of Parliament to refrain from opposing every single option.Why, then, do we still fetishise debate? Perhaps because the spoken word seems to us somehow more authentic than the written. The superstitious valuing of speech over writing – often called “logocentrism” – is a long-lived prejudice in western civilisation. Indeed Plato’s Socrates, who is so suspicious of rhetoric, is also suspicious of writing. In the Phaedrus he says that writing is only useful to remind oneself of what one already knows. The problem with written words, he says, is that they can’t answer back when you question them. But we only know this because Plato wrote down his dramatisations of philosophical discussions, in which the characters could indeed answer each other back.

It takes 30 seconds to make a misleading scientific statement and 30 minutes to refute it George Monbiot

Might it then be a cause for hope, rather than lamentation, that today’s teenagers apparently prefer texting one another to speaking on the phone? Maybe logocentrism is on the way out; and if so, good riddance. Writing is more accountable to evidence, and is also immune from the interpersonal emotional factors that autocratic orators have always relied on. “Demagoguery is dialectical,” says Dimock. “You can’t have a demagogue without an audience.” Indeed, Trump’s rallies, far from being deliberative inquiries into policy, are more like the valedictory concerts of a much-loved comedian, with the adoring faithful cheering every nonsensical catchphrase.

Last year, IBM Research unveiled Project Debater, an AI tool designed to be able to debate either side of a question against a human opponent. Arguing with human opponents (from IBM) about, for example, whether space exploration should be subsidised, and whether we should increase the use of remote medical procedures, the AI, speaking in a synthetic female voice, did well enough that the audience judged it better at conveying factual information.

Under the hood, this is a synthesis of various computational modules including speech recognition (to respond to human opponents), and the analysis of a vast corpus of newspaper and magazine articles, from which the machine draws not only its facts but also its arguments. It doesn’t create any new lines of reasoning, but only selects those made by humans it judges the best. On IBM’s website, we learn that the system doesn’t actually “learn a topic” in terms of understanding it, but it is “very good at quickly creating a persuasive narrative based on available data”. It is designed, IBM says hopefully, “to help expand minds and help people see more than one side of an issue”. We can only wish them good luck.

In a different way, Project Debater does point towards one better potential future. We could delegate the job of live competitive debating entirely to robots, and even construct compelling newstertainment gameshows around the spectacle. We could then get on with discussing our problems using more careful and illuminating forms of communication, such as the patient, probing interview, or the free-range panel discussion – or, of course, the peerless technology of writing.