What’s your poison, people sometimes ask, but Gabor Maté doesn’t want to ask what my poison is, he wants to ask how it makes me feel. Whatever it is I’m addicted to, or ever have been addicted to, it’s not what it is but what it does – to me, to you, to anyone. He believes that anything we’ve ever craved helped us escape emotional pain. It gave us peace of mind, a sense of control and a feeling of happiness.

And all of that, explains Maté, reveals a great deal about addiction, which he defines as any behaviour that gives a person temporary relief and pleasure, but also has negative consequences, and to which the individual will return time and again. At the heart of Maté’s philosophy is the belief that there’s no such thing as an “addictive personality”. And nor is addiction a “disease”. Instead, it originates in a person’s need to solve a problem: a deep-seated problem, often from our earliest years that was to do with trauma or loss.

Maté, a wiry, energetic man in his mid-70s, has his own experience of both childhood trauma and addiction, more of which later. Well-known in Canada, where he lives, he gives some interesting reasons why Britain is “just waking up to me” and his bestselling book In the Realm of Hungry Ghosts. There’s a generational conflict here, he says, around being open about past trauma: he cites Princes William and Harry opening up about their mother’s death, and says it’s something the Queen’s generation would never have done. He applauds the new approach: “I think they [the princes] are right to be leading and validating that sense of enquiry, without which life is not worth living.”

The infamous British stiff upper lip is something Maté has watched with fascination over the years. Born of our imperial past, he says, it was maintained for as long as there was something to show for it. Boarding school culture and traumatic childhoods played out into dominance of other countries and cultures, giving the “buttoned-up” approach inherent value. But once the empire crumbled, lips quavered.

“With rising inequality and all the other problems there are right now,” he says, “people are having to question how they live their lives. People in Britain are beginning to realise they paid a huge price internally for all those suppressed emotions.”

And addictive behaviour, though damaging in the medium or long term, can save you in the short term. “The primary drive is to regulate your situation to something more bearable.” So rather than some people having brains that are wired for addiction, Maté argues, we all have brains that are wired for happiness. And if our happiness is threatened at a deep level, by traumas in our past that we’ve not resolved, we resort to addictions to restore the happiness we truly crave.

He speaks from experience: Maté is a physician who specialised in family practice, palliative care and, finally, addiction medicine. He became a workaholic and lived with ADHD and depression until, in his 40s and 50s, he began to unravel the root cause – and that took him all the way back to Budapest, where he was born in January 1944. Two months later, the Nazis occupied Hungary: his mother took him to the doctor because he wouldn’t stop crying. “Right now,” the doctor replied, “all the Jewish babies are crying.” This is because, explains Maté, what happens to the parent happens to the child: the mothers were terrified, the babies were suffering, but unlike their mothers they couldn’t understand what the suffering was about.