Politics is almost entirely in the eye of the beholder. Obviously, conservatives, libertarians, progressives and environmentalists have different ideas about government. But the clash goes much deeper. Political disagreement isn't really about politics. It is about competing worldviews; different conceptions of ethics, morality, relationships and communities.
With that in mind: how polarised do you think Australian politics has become? Have we really hunkered down into bitter, warring camps on issues such as climate change and refugees?
How you answer says a lot more about you than anything else. A fascinating paper just published in the Journal of Personality and Social Psychology says the more radical your politics are the more radical you imagine everybody else's politics to be. The authors found ''people project their own polarisation onto others''.
Projection is a basic human trait. We believe others share more of our attitudes than they do. If we like dark chocolate, we assume others like it, too. If we like walks in the park, we assume others do, too. Humans are social animals: it's important that others validate our preferences.
In politics, this doesn't necessarily mean we think everybody agrees. (Although psychologists have found we imagine a false consensus about everything from animal rights to nuclear energy.) But it does mean we assume everybody is as passionate as we are. So, when radical partisans encounter disagreement, they see aggressive conflict and polarisation.
Projection confuses virtually every aspect of politics. It makes us assume a greater degree of consensus on the big moral questions than there really is. When that consensus is shown to be an illusion, it breeds hostility.
In a book released in March, The Righteous Mind: Why Good People are Divided by Politics and Religion, the American academic Jonathan Haidt explains the psychological basis of our political divide. Using thousands of interviews, Haidt discovered that progressives had three moral foundations for their political views. But conservatives had twice as many.
Progressives are driven by compassion, fairness and liberty. Conservatives share those ideals, but they add group loyalty, respect for authority and ''sanctity'' - that is, a sense that some things, like marriage or the flag, should be sacred and untouchable. Both sides have to manage trade-offs between their ideals, but conservatives have more ideals and have to manage more trade-offs. This explains a lot about why left and right are at loggerheads.
Haidt argues that conservatives cope best when they project their own moral beliefs onto progressives, they recognise compassion, fairness and liberty, and identify that loyalty, sanctity and authority are missing.
But when progressives look at conservatives, they get bewildered. Projecting their moral framework onto conservatives doesn't seem to explain much. So, progressives offer different explanations: conservatives must be selfish, heartless.
Kevin Rudd famously wrote that free market conservatives dressed greed up as economic philosophy. He might just as well have said he was completely mystified that anybody could disagree with him. Rudd could not reconcile his moral philosophy with the beliefs of others. His projection failed. And people attack what they cannot understand.
Rudd's successors are no better. Julia Gillard and Wayne Swan claim to represent the ''fair go''. Perhaps this excites Labor's base, which can smugly fantasise that: if the left like fairness, the right must like unfairness. But conservatives like fairness, too. For them, fairness manifests as an interest in working hard and not relying on charity - or welfare. When progressives look at their opponents, they don't realise the right has a different and legitimate moral framework.
And when radical partisans of all stripes confront their opponents, they imagine a great political divide, and become more radical in response. When we believe our values are the only possible ones, we make politics more hostile than it need be. We're angry, not because we think we're all different but because we think we're all alike.
Chris Berg is a research fellow with the Institute of Public Affairs. Twitter: @chrisberg