Boiled down, political prognostication involves a small number of pundits who scour the sushi-train of political events, claiming to know the minds of a majority who have taken no such interest.
You can see the problem, right? These two groups have not been watching the same thing and could hardly share fewer interests.
In practice, it is nigh-on impossible to know which big spending announcements, SMS scandals and squalid internal brawls, have lingered in the public mind.
One thinks of the Heisenberg's "uncertainty principle" which essentially said that the very act of observing could alter the subject, or at least render it unreliable.
Of course there are public opinion surveys to help guide such judgments, but these polls emerged from the last election in worse shape than the defeated Labor Party.
As another Nobel Laureate, Brian Schmidt, noted after the 2019 election, that there had been 16 polls published during the campaign itself, and every single one of them predicted "Labor winning 51 per cent or 52 per cent" of the two-party-preferred vote.
Days later, the Coalition won 51.5 per cent of the national vote to Labor's 48.5 per cent.
Schmidt argued that sampling errors had been routinely undervalued and suggested that pollsters may have succumbed to a very human tendency to converge thus compounding any such faults. As he said, it wasn't the maths that had lied.
Another guide for commentators is more qualitative than quantitative and comes from comparable events of times past.
Yet immediately we can see another problem because pertinent history - i.e. the aforementioned 2019 upset election result - may obscure more than it reveals. The similarities are obvious enough but how do we weight the differences?
One constant which hasn't applied since 2007 is that the successful candidate in 2019, Scott Morrison, remains in place at this election.
In the campaign itself, Morrison performed surprisingly well, overcoming an entrenched poll deficit of similar scale to the one he faces now.
Ergo, it seems safe to posit that the same PM facing the same opposition party in eerily similar circumstances, could repeat this success. Yes?
If you believe Morrison, this is virtually certain.
However, look closer and you can see that even before factoring in his opponents, there have been unfavourable changes on the Morrison side which might by themselves finish him off.
Where voters didn't know Morrison well in 2019, they might see straight through him after three years in office.
On Labor's side there are bigger changes - not least of which is a new leader.
On the face of it, switching to Anthony Albanese is a pretty crucial variable in itself, although how crucial remains to be seen.
Equally importantly, Labor has learned. The new leader has conscientiously plotted a different course from Bill Shorten's ambitious suite of taxing and spending reforms by adopting a streamlined and cautious approach to policy and presentation.
This may have disappointed some left-of-centre voters (and frustrated the hell out of Morrison) but Albanese's backers argue it exposes Labor to far less misrepresentation than it had invited in 2019.
Some however, fear it also leaves Labor short on the inspiration side of the equation, setting the election up as an unimaginative choice between Tweedledum and Tweedledee.
This is a finely balanced judgment. As historian Professor Frank Bongiorno reminded me, Labor has rarely won through without making itself the story, without putting forward a bold vision and courting a degree of controversy. Think Gough Whitlam in 1972, Bob Hawke in 1983, and Kevin Rudd in 2007.
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Albanese, a 25-year parliamentary veteran, knows this, and knows too there are expectations on Labor to grab the imagination, and shake up long-neglected areas of the economy and society.
He has concluded however that Australians are actually quite cautious, and are generally disinclined to change governments, noting that Labor has achieved it only three times since the Second World War (the instances referred to above).
He reasons that in asking Australians to make that leap, they must also feel safe to do it, assured that the party to which they are entrusting power is sober, its policy solutions are well-founded, and its methods, orderly.
This explains his frequent references to Hawke's breakthrough win in 1983 on the promise of national unity, traditional cabinet government, economic advancement, and consensus. And it explains the echoes of Rudd's economic conservatism - framed by the latter's declaration against John Howard, "this reckless spending must stop".
Labor's low-friction approach reached its apotheosis in the swift legislative passage of the fourth Frydenberg budget a couple of weeks back despite strong internal reservations.
But Albanese must know there are limits to this approach and those limits are now at hand.
Once the campaign is on, he cannot propose a change of government via a campaign that merely cycles along in the Coalition's peloton.
He must now use the invitation of the formal contest to speak out more forcefully about the fairer, more just, more creative 21st century nation that Australia can be.
That will build on the significant policies already announced on childcare, aged care, skills and training, gender equality, and the environment.
But it must also speak to a cultural and social impatience for the next chapters in Australia's advancement - especially in respect of the 2017 Uluru Statement from the Heart.
He must speak to an Australia that is not merely an economy, or a market, or a soulless federation, but a modern and ancient nation, a work in progress towards something higher, fairer, and more sustainable.
And a nation that can step forward internationally because it has finally and honestly reconciled with its past and its challenges.
Mark Kenny is The Canberra Times' political analyst and a professor at the ANU's Australian Studies Institute.