Most of us still like to think of ourselves as people who can talk things through.

We say we value openness, nuance and honest disagreement. We teach our children to use their words. We tell our students universities are places for inquiry. We tell ourselves democratic life depends on the exchange of ideas rather than the silencing of them.

And yet, when a subject becomes morally charged, many of us do not become more thoughtful. We become more guarded. We reach for certainty, or we retreat into silence. A question that once might have opened a conversation now risks being heard as a provocation. A moment of hesitation can be read as moral weakness. An attempt at nuance can sound, to someone else, like evasion, indifference, or betrayal.

That is part of why so many Australians feel conversation has become brittle. The difficulty is not simply that we disagree. Disagreement is a normal feature of any free society. The difficulty is that disagreement now often feels harder to contain, harder to interpret and harder to survive.

Many people enter contentious conversations with the sense that they are not stepping into a discussion so much as into an atmosphere of scrutiny. What they say may be weighed not only for its content, but for what it seems to reveal about their loyalties, their values and their character.

This matters well beyond the realm of politics. You can feel it in classrooms, workplaces, and around dinner tables.

It shapes what people are willing to ask, what they are willing to admit they do not know and whether they feel able to revise a view in public without humiliation. It narrows the space in which thinking can happen out loud.

The result is not just louder conflict. Often it is thinner conversation. People speak in polished positions rather than unfinished thoughts. They reach more quickly for slogans. They avoid questions that might be misread. They become less candid, less exploratory, and less willing to risk complexity in front of others.

In a country like Australia, which prides itself on plain speaking, that should concern us.

Many people describe the problem as polarisation: we not only disagree more but increasingly distrust those with whom we disagree. That is part of it. The deeper shift lies in the conditions under which we speak – conditions that make nuance costly and certainty feel safest.

Several forces drive this.

First, is the cumulative weight of public shocks. Violent incidents, hateful acts, campus controversies and moments of collective grief reshape the emotional climate. In Australia, where migration ties families across continents, distant conflicts feel immediate.

Our brains are not built to absorb this volume of distress. The result is cognitive overload: a strained system that struggles with complexity and defaults to certainty. One feature of this is binary bias – the tendency to reduce ambiguity into opposites: good/bad, right/wrong, hero/villain. Yet real people and conversations rarely fit such categories.

This overload is not only cognitive but visceral. When disagreement touches on core aspects of our identity, the brain’s........

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