Liz Truss loves maths. She loves it so much that she used to fire mental arithmetic questions at civil servants during meetings, and once told an audience of female high-flyers that her best advice for their ambitious daughters was to study the subject.
She loves maths so much, indeed, that she approaches political decisions like an equation to be solved.
The maths professor’s daughter works methodically through every possible option, including some that others would consider beyond the pale; she likes to test every argument, sometimes to exhausting lengths. (As one of her aides used to joke: what’s the difference between a rottweiler and Liz Truss? A rottweiler eventually lets go.)
Her logical, dispassionate mathematician’s approach makes her a formidable negotiator and an unsentimental strategist, swift to abandon positions that no longer serve her.
Yet those who know her best say that with it comes a curious emotional detachment, or inability to factor into her calculations how things feel to other people, which is only now being exposed.
She can be good company in private, funny and lively. But when colleagues mention her “faintly awkward” manner, or even call her “as close to properly crackers as anybody I’ve met in parliament” (Dominic Cummings, no stranger himself to being called something similar), this particular disconnectedness is often what they mean.
It’s shaped the campaign of the woman still most likely to be Britain’s next prime minister, barring a political earthquake, and may soon shape Britain's future.
The first slip was her regional pay policy, ditched amid predictable outrage at the thought of lower salaries for teachers and nurses in the north of England.
The second and most serious was pledging to help with fuel bills by lowering taxes, “not giving out handouts”. (She now claims both policies were misunderstood, and that she wasn’t ruling out direct grants.)
Even those sympathetic to Truss expect a U-turn on those handouts, in a climate where focus group participants talk about moving their elderly parents in with them for the winter because it’s the only way everyone can afford to keep warm.
“Politics is about emotions, it’s not a mathematical equation,” says a former colleague who has worked closely with her.
Truss is enviably calm in a crisis, this colleague adds, in part because she strips the emotion away from the issue.
But the trouble is that sometimes emotion is key, and empathy matters. What this means for the country, if she does end up leading it through a crisis of staggering proportions, remains poorly understood.
With her extensive cabinet track record and burning ambition, she’s not “the Tory Corbyn”. But nor is she just “Boris in a dress”, although her indulgence of the ridiculous notion that the media are to blame for Johnson’s wilfully self-inflicted downfall suggests similarly Trumpian tactics.
She lacks Johnson’s taste for high living — any emerging scandals won’t involve gold wallpaper — or his need to be loved; she has taught herself not to care what people in politics think of her.
But where Johnson never seemed to know what to do with his enormous majority, Truss is a workaholic policy geek whose government would be driven by her manic energy. In the worst-case scenario, she could do more damage than he ever did.
“She’s a contrarian. Just because 90% of people tell her, ‘This way is the way’, she’s not inclined to accept that. That’s not a bad quality, but it can be a problem if it’s taken too far and if your default setting is that the orthodoxy is always wrong,” says a former No 10 staffer, who sympathises with her argument that the Treasury isn’t always right but nonetheless points out that consensus can be the consensus for good reason.
Yet the paradox of Truss is that in some ways, she can be astonishingly flexible.
Under David Cameron she was a card-carrying centrist Cameroon, part of what in his memoirs he called his future “dream team”, alongside Nicky Morgan, Matt Hancock and Anna Soubry. Now she’s the darling of the hard right.
Three years ago, she backed building on the green belt so young people could own a home; not any more.
She has passionately championed flexible working for parents all her career, yet now indulges Jacob Rees-Mogg’s war on working from home. An unenthusiastic remainer in 2016 (George Osborne talked her out of backing leave in the referendum, a decision she regretted when leave won) she was a no-deal-beats-a-bad-deal Brexiteer by the time power began ebbing from Theresa May to Johnson less than three years later.
Her belief in low taxes, and public spending to match, is much more authentic and consistent. (She was a hawk-eyed chief secretary to the Treasury, challenging sums conventionally regarded as peanuts, and still diagnoses the NHS’s problems as too much bureaucracy rather than not enough money.)
But instead of growing the economy and using the proceeds to cut taxes as Cameron advocated, now she argues for doing the easy bit first and hoping growth follows.
“She is wherever the power is, which I find extraordinary,” a former cabinet minister says.
“But on the other hand, those people tend to win.”
She might well seek to recalculate once in No 10, ditching unpopular positions without embarrassment as she has done before. Yet her room for manoeuvre would be tiny.
The Tory right put her where she is now and they won’t tolerate backsliding over tax cuts, or over the Northern Ireland protocol – although trade wars with Europe would only deepen the coming recession – or threats to quit the European court of human rights.
As a prime minister facing multiple complex crises simultaneously, she’d struggle to operate in her usual methodical but time-consuming way, all while judging the public mood minute by minute. If anything, mis-steps might come thicker and faster.
There are still people who can’t take Liz Truss seriously, but it’s this kind of sneering that has arguably been the making of her.
When critics mocked her speeches, she set about methodically overhauling her presentation skills. Even as she built a power base in plain sight, she was never deemed sufficiently threatening for either Johnson or May to sack her.
Rishi Sunak visibly underestimated how much homework she’d done on the Tory membership. Now she’s having the last laugh, except this isn’t funny.
She could be running Britain in four weeks. If that’s not serious, what is?
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