The art of persuasion depends on understanding the point of view of someone who disagrees with your most favoured opinions. Otherwise you end up being just a cheer-leader for people who happen to agree with you already.

The art lies in imagining a good person (intelligent, kind and sensible) who isn’t on your side and then trying to convince such a person of the merits of your position.

In the last few days we’ve had two star examples of not doing this. Germaine Greer — in her discussion of male aboriginal rage — writes and speaks as if only an evil person could disagree with her.

Then, writing in The Australian, Janet Albrechtsen lashed Clive Hamilton and his brand of cultural pessimism: only a doltish depressed communist could have any sympathy whatever with his anxieties about consumerism.

The interesting thing is that these examples come from opposite ends of the political spectrum. They don’t share any policy assumptions; what they share is the self-serving conviction that only an idiot could disagree with them.

This isn’t just factually wrong, it’s also poor tactics. The aim of polemical writing is to convert people. And shouting, mocking and mentally ordering people about isn’t usually a very good way of doing this – ask any marriage counselor.

Erroneous views are usually exaggerated, distorted and misleading versions of good ideas. But there’s a good point in there.

Janet writes as if there were no such thing as greed, as if no-one ever messed up their own life through over-spending on things they didn’t really need.

Clive’s hair-shirt attitudes may well be excessive, but perhaps he is onto something. In any case, can Janet learn to speak helpfully to people who do think he is onto something? If he has the wrong solution to his worries, what would a better solution look like?

Germaine identifies something important: self-destructive rage is a truly terrible thing, in which people really do get trapped. But it’s only natural to want to escape from the rage of others especially when you haven’t yourself caused it. The rage of others is frightening and profoundly off-putting. Could Germaine learn to speak to people who have this very understandable response?

The key point is this: a lot of disagreement isn’t about facts. It’s about feelings — dislike, boredom, indifference. You can’t be argued out of those emotions; you need to be coaxed, tempted, flirted with, have your inhibitions soothed. I know it sounds perverse, but I want Germaine and Janet to seduce me.