Donald Trump's victory was the most dramatic demonstration yet that liars can win elections. All he had to do was demonize reason and fact as the province of hated "elites."

This is scary, for all countries and for reasons beyond the frightening contents of the Trump platform itself.

The problem isn't that journalists are letting candidates' falsehoods go unexamined. Some are, of course. But we live in an age of abundant fact-checking. Mainstream newspapers and dedicated non-partisan websites researched and reported on the truth of what Trump and his rival Hillary Clinton said every day on the campaign. The excellent reporter Daniel Dale at the Toronto Star catalogued every Trump falsehood. It's all there.

And yet Trump was, perversely, lauded for "telling it like it is."

Dunning-Kruger effect

As psychologist David Dunning himself has written, Trump's rise relied at least in part on the so-called Dunning-Kruger effect. People who know a very little about a subject – whether it's the stock market, the rules of grammar or a political policy – are more confident in their expertise than people who know a lot. "The problem isn't that voters are too uninformed. It is that they don't know just how uninformed they are," writes Dunning.

The cure for Dunning-Kruger is, paradoxically, more knowledge. But you can't convince someone to read a fact-check or an explainer with an open mind if they already think they know it all, and especially not if the person they trust is telling them everyone else is conspiring to trick them.

So who can fix this, if journalists' tools are blunt against it? Well, political parties might give it a try.

At the moment, the celebration of gut feelings over evidence is the favourite strategy of the political right across North America (although over time, both the right and the left have been guilty of it.) Talking-point populism has had some success in Canada. The late mayor of Toronto, Rob Ford, made a career on repeating the same wrong or grossly misleading statements.

"To say that it is self-evident is to say that it is known to be correct without argument and without explanation," Joseph Heath writes in his book Enlightenment 2.0. "Thus, making common sense the core of one's political ideology amounts to a pure privileging of intuition over rational thought, of 'gut feeling' over deliberation, and of heart over head."

Fittingly, "common sense" as a talking point has come to mean its own opposite: rather than shared rationality, it now means pure emotion rooted in an individual person, severed from other people's expertise and experience. It is, therefore, the opposite of the traditional conservative project, which seeks to integrate flawed individuals into communities, institutions and traditions, for the common good.

Basis of human rights

In The Origins of Totalitarianism, Hannah Arendt wrote, "Only because we have common sense, that is only because not one man, but men in the plural inhabit the earth can we trust our immediate sensual experience." True common sense is the opposite of isolated, divided individuals trusting their guts. It is the mutual recognition: I exist, and you exist. It is the basis of human rights.

The good sense of ordinary people is the foundation of democracy; not for nothing was Thomas Paine's pamphlet titled "Common Sense." When that fails – when facts and arguments become meaningless, when empty slogans and invented bogeymen win elections – democracy fails, and totalitarianism marches in.

Canada's Conservative party is choosing a new leader and a new direction. It is in the midst of the same tug-of-war that divides every right-wing party these days: the "elitist" libertarians and evidence-based moderates, versus the populists who want to talk about values and common sense.

The Conservatives can say no to a lazy dependence on slogans, writes Kate Heartfield. (Liam Richards/Canadian Press)

Perhaps there's a way for the Conservatives to honour both head and heart – to appeal to values without abandoning reason and embracing bigotry. The Conservatives can say "no" to a lazy dependence on slogans, on the nearest convenient enemy – a dependence they know full well encourages racism, sexism, anti-Semitism and homophobia. They can try to come up with a less destructive appeal to "common sense."

True common sense declares: We're going to look out for each other. We have a responsibility to our communities: to make our institutions as competent as they can be, our services as effective, our common places safe for all. We work hard, we help our neighbours, and we accept nothing less than respect, honesty and decency.

These are not left-wing or right-wing principles; the paragraph above is old Canadian Toryism in new clothing. But it means having the guts to abandon easy, reckless wedge politics.

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