Professor Jordan B Peterson’s apartment smells of meat. It’s 8am and his wife, Tammy, is fastidiously slicing a pile of steaks, frying them, and shovelling the unadorned results into a stack of Tupperware containers.

It was Tammy, his childhood sweetheart who now works full-time for Peterson PLC, who greeted me when I arrived at his serviced apartment near Holborn, leading me into an unremarkable, open-plan room with laminate floors and a depressing view. It seems almost laughably austere for a man who makes $80,000 a month from online donation site Patreon, plus royalties for his million-selling book 12 Rules For Life.

Peterson, for the uninitiated, is probably the most influential conservative thinker in the world today – although, as he’s keen to point out, he doesn’t have a great deal of competition. An academic and clinical psychologist by trade (he ran a full-time practice until last year), his YouTube lectures offering interpretations of bible stories and no-nonsense advice for young men are routinely watched by millions, and he sells out auditoriums across North America.

Two years ago things were very different. A professor at the University of Toronto, he had a moderate profile on Canadian television, and had written an academic book that sold as well as academic books tend to. Everything changed when he spoke out against a law that could – in theory if not in practice – compel Canadians to use trans people’s preferred gender pronouns. He made a video decrying the “attack on free speech” and was briefly suspended by the university.

He had struck a nerve. Suddenly someone was articulating what millions of conservatives had always felt in their gut – that political correctness had gone mad; that leftie, snowflake, Social Justice Warriors were dictating what good honest people could and couldn’t say; that traditional values were under attack from a permissive minority.

He soon gained a cult following, predominantly among young white men, and he says he’s received thousands of letters from people whose lives he’s turned around. One particularly tragic post on Reddit is entitled “I’m 40, can Jordan Peterson still help me or is it too late?”. He chalks his demographic down to YouTube’s largely male user-base, and says it’s changing as his celebrity shifts from the internet to the wider media landscape.

But it’s probably not a coincidence that someone who denies the existence of the patriarchy (simply a symptom of male competence) and white privilege (merely “majority privilege”), tends to appeal to white men. Having said that, it was a female friend who insisted I read 12 Rules, calling Peterson “the world’s dad”.

The crux of his philosophy is that society is largely a result of biology. The structures in place – traditional gender roles, for instance – existed long before we were conscious of them; before humanity – before even flowers, apparently. Attempting to mess with things – by, say, encouraging more women to be engineers – isn’t only futile, it’s damaging. If you look closely, he says, you can see this natural order reflected in the stories, myths and symbols we use to define ourselves as a species, from Adam and Eve to Yin and Yang.

All of this has made him a target for those on the left, who see him as the acceptable face of – or at least the gateway drug to – misogyny and white nationalism. “Leftists make out that there’s something wrong with me,” he sighs. “I’m not part of the radical left, [so] I must be part of the far-right, which is absurd.”

His detractors mock his trademark combination of folksy advice – “stand up straight”, “tidy your room” – and Jungian psychology, once summed up as “Jung mixed with stuff your da’ might say”. Any such criticism usually receives a swift and vitriolic response from his legion of fans. “Anyone who has gone after me has paid a very heavy price,” he tells me, stressing the last three words in what strikes me as 80 per cent boast and 20 per cent threat.

An ill-tempered clash with Channel 4 News presenter Cathy Newman, during which Peterson batted away a barrage of accusations, leaving the reporter momentarily speechless, ended with security experts being hired over fears for her safety. The clip has been watched more than 10m times. “She was trying to win an argument with some hypothetical person who wasn’t even there,” he says, shaking his head.

Whether you’re on the left, the right, or somewhere in-between, there’s a magnetism to Peterson. When people first discover him, they often describe falling down a “rabbit hole”, staying up all night watching his videos, poring over newspaper coverage, admiring (perhaps grudgingly) his calm, unflinching debating style, delivered in a voice that’s been likened to that of Kermit the Frog.

The scene of domesticity in the Holborn apartment – wife silently tending the hob, the low crackle of frying meat – is incongruous with the lion’s den I’d expected. Peterson, 56, is slight and foppish, dressed in forest green chinos and a slim-fitting blazer, grey hair pushed back into a quiff. He spreads his arms over the back of the sofa, making himself bigger like a pigeon ruffling its feathers. He crosses his legs extravagantly and taps his foot when he dislikes a question. It’s hard not to analyse a psychologist.

I’m interested in how fame has changed him. Have the last 18 months made the man who wrote the rules for life happier with his own? “Oh no. Definitely not,” he says without a pause. “There are a lot of complex reasons for that [but] I’m in contact with millions of people and a large number of them have had their lives turned around by listening to my lectures and reading my book…”

Okay, but what about your happiness? His foot taps. “Well, my job was in danger and my clinical practice could have gone… I’m difficult to take out as I have multiple income sources. But it’s been very hard on my family, although they’re resilient and have been through much worse. This was a big storm compared to a hurricane. And I’ve been ill quite a lot, so that’s also complicated things.”

An autoimmune disorder runs through Peterson’s family, with his daughter Mikhaila particularly badly affected. At 17 she had both a hip and ankle replacement because of aggressive arthritis. There were fears she might die. She went on a strict, ketogenic-style diet (mostly meat and greens) and her symptoms disappeared. Peterson’s own symptoms, including chronic insomnia, psoriasis and gum-disease, were similarly alleviated when he started the same diet – hence the tubs of meat.

“I’m insanely busy,” he continues. “I was busy before but it’s a whole new level now. I’ve always had three jobs, essentially, but now… I’m travelling all the time. And I have to watch everything I say. I’ve had a lot of people come after me in the last year and a half – journalists, academics, mobs. I find it stressful… because I’m actually not a particularly combative person.”

He says he works 16 hours a day, seven days a week, and sleeps only six hours a night. “It’s a minority taste. I operate best when I’m working flat out but not everyone is temperamentally inclined to that.”

The hardest part isn’t the travelling, or the long hours, however. The hardest part is speaking to journalists. “Many of them are combative, and I’m not really interested in that. It takes a lot of psychological effort to defend myself. It’s not a pleasant position to be in. But people are more polite than they used to be; when I went to Australia, the publicist said the Cathy Newman interview had been circulated as an object lesson in what not to do.”

For someone who hates talking to journalists, however, he spends an awful lot of time doing it. He recently invited a New York Times reporter into his home for two days to watch him work. The result was a car-crash by any standards; he was painted as a kook, and caused a stir when he suggested the solution to violence by so-called “incels” (involuntarily celibate young men) was “enforced monogamy”.

He later clarified that he meant “enforced” by societal proclivities towards institutions like marriage, rather than by physical force, but a man who espouses choosing your words carefully (Rule Number 10: Be Precise in Your Speech) should have known better. He still tweeted a link to the article. Twice.

It strikes me that there are two sides to Peterson. One the one hand, he’s the quintessential academic. He speaks incessantly about “neo-Marxist post-modernists” invading university campuses (he’s even thinking of starting his own online university). He fills his house in Toronto with Soviet propaganda; a reminder, he says, of the evils of extremism (apparently Mikhaila is named after Mikhail Gorbachev, which is a bit like Jeremy Corbyn calling his daughter Blair).

His lectures on mythology and religious allegories are lively and fascinating and a bit mad, in the way the best academia often is. You can easily imagine him stalking the wood-panelled corridors of an Ivy League university. It makes you ponder the strange alchemy of time, place and situation that made such an eccentric, bookish man a superstar.

But there’s another, more cynical side, one that’s keenly aware of what will keep him on the news agenda. He complains about being lumped together with the alt-right – “the only people who think I’m part of that is the left, the alt-right doesn’t” – yet he often sings from a suspiciously similar hymn sheet.

After our interview, for instance, he tweeted support for thuggish EDL founder Tommy Robinson, who had just been jailed for contempt of court after almost derailing a long-running trial. Another time he instinctively sided with the American baker who refused to make a wedding cake for a gay couple, until the person interviewing him pointed out that restaurant owners once used the same argument for refusing to serve black people. For a self-proclaimed radical thinker, these are pretty tawdry waters to be swimming in.

I ask if he has any regrets about rising to fame by opposing a law designed to make life easier for trans people – would he have preferred a different hill to die on? “Yeah, but it’s not a reasonable hope,” he says, foot tapping. “Encroachment on free speech is always done in the name of compassion for the oppressed. If it hadn’t been the trans people it would have been some other oppressed group and I’d have been in the same situation. The Nazis couched their euthanasia programme in compassion – the old ads said you were doing these people a favour, because they were suffering bitterly.

“One of the things we should always be on the guard against is assuming that your benevolent intervention is going to have the desired effect. Systems are too complex to predict. So was it unfortunate? Well, it caused a scandal. Whether it’s unfortunate is hard to say. It was stressful.” This very much fits the Peterson narrative, him bearing the cross of common-sense conservatism in the face of outrageous slights from the radical leftists and the neo-Marxists and the postmodernists.

I look up and Tammy is gesturing towards the door. The meat is all neatly packaged away. Another dreaded journalist is waiting in the wings, ready to test Peterson’s patience. My lasting impression is of a deadly serious man, rather cold, unwaveringly committed to his ideas, perhaps not entirely comfortable in his newfound role as the global face of conservative thought.

As I’m being ushered out, one of our company execs, who had tagged along for the interview, pulls out a copy of 12 Rules for Peterson to sign. “You’ve made me a

better parent,” he says, requesting a selfie. Peterson cracks a smile for the first time all morning, happy to be in the presence of a true believer. I guess that’s Rule Number 7: Make Friends With People Who Want The Best For You.