We knew things were pretty dire, but a new poll has put some numbers onto our fears.

The “Citizen’s Agenda” survey from the University of Melbourne has found that voters are “pretty appalled” at the standard of political debate, with 57% of voters saying things are getting noticeably worse. Not surprisingly, the overall level of interest in politics is sliding as well.

These numbers underscore the numerous criticisms made in recent years by people who’ve been in the political trenches. Diverse luminaries such as Barry Jones, Lindsay Tanner, and Malcolms Fraser and Turnbull have complained that public political debate has never been so bad.

What’s happening here? Why, when Australians are more educated and connected than ever before, is political discourse being degraded?

A natural instinct is to search for somebody or something to blame – some dark force degrading public discourse for its own greedy purposes. The news media and politicians are popular suspects; others point to campaign managers, advertisers and spin merchants; or to television, the internet, or mobile devices.

Alternatively, we can view the problem through the lens of a simple and familiar metaphor: that people are, increasingly, just not playing by the rules.

Consider chess – a game with a limited set of clear and accepted rules. Rule-governed play typically delivers a clear outcome, with everyone agreeing who won or lost.

If we think of public debate as a kind of game, then the rules are the laws and conventions of logic and disputation, as articulated by logicians and rhetoricians over the centuries.

Public debate is of course not a game. It is a deadly serious business, often literally so. But that just makes it all the more important that people respect the rules.

So what’s going wrong?

One problem is that people often don’t really know what the rules are. For the most part, they have never been educated in logic and disputation, and would be pressed to give any account of the rules. It’s hard to play correctly when you’re foggy about what’s OK and what’s not.

Second, there will always be incentives to cheat. This can be straightforwardly foul play, like a rugby player throwing a punch under cover of a maul. Witness climate change deniers who trot out the argument that temperature hasn’t increased since 1998, no matter how many times its flaws have been decisively exposed.

Worse than breaking the rules is subverting them. This amounts to changing the game, or even destroying the game entirely. This sounds extreme, but Paul Krugman and others have been accusing US Republicans of precisely this gambit – of “refusing to live in an evidence-based world.”

Third, there’s no effective umpire. There’s no authority or expert whose role is to judge what’s legitimate and whose calls are accepted by all the players.

Finally, we all suffer from the problem that our mental machinery is poorly designed for the task. Public debates can get complicated, and the brains bequeathed to us by evolution don’t have enough “RAM” to comprehend the evolving state of play. And we are all subject a wide range of cognitive biases which reliably lead us to make errors of logic and to violate norms of constructive debate.

Surveying these factors, the prospects for any substantial improvement seem remote. Three – the incentive to cheat, the lack of an independent umpire, and cognitive limitations – are deep features of what is sometimes called “the human condition.” Education can in principle help people know what the rules are, but is a slow and unreliable way to effect social change.

Fortunately there is another option.

Think of public debate as taking place in various arenas. The floor of parliament is one; commentary in the mainstream media is another. The internet has allowed the emergence of new online arenas such as the blog- and Twitter-spheres.

The subtle but critical point is that these various arenas promote or discourage playing by the rules in different ways. Twitter, for example, makes complex chains of reasoning almost impossible, and promotes follow-chambers in which contrary views are all too easily ignored or ridiculed. Another example is comment forums on news websites, which encourage trolling by having the discussion open to all, and allowing anonymity (via pseudonymity).

However the programmability of the internet makes possible a great variety of arenas, and new ones aimed at improving public debate, and democracy more broadly, are proliferating around the world. Oursay, a partner in the Citizen’s Agenda project, is just one example, increasingly prominent in Australia.

Some of these forums are being designed to gently guide participants towards higher quality participation in political debate. One way to do this is to scaffold “nudge” participants to stick to the rules more often, perhaps by giving greater prominence to those who do.

An example is the German “Faktencheck” (Fact Check) project, which works in collaboration with mainstream media entities such as Frankfurther Allgemeine Zeitung to host public debates on current political issues.

Our project, YourView, is another example.

Forums such as these will continue to evolve and play an increasingly large role in public political debate. Lindsay Tanner has spoken of a “revolt of the engaged”. This revolt can go beyond just online fundraising and petitioning; if the forums are designed correctly, it can start to halt or reverse the slide in the quality of public political debate.