In his latest book, human rights lawyer Mr Dexter Dias identifies 10 types of people who can help us better understand ourselves.

Mr Gareth Myatt was just three days into a 12-month sentence at Rainsbrook Secure Training Centre, a privately run juvenile detention facility near Rugby, England, when he was fatally restrained by three prison officers using the “seated double embrace”, which is no longer permitted for use on young people in the UK. While he was being pinned down, Mr Myatt repeatedly protested that he couldn’t breathe. If you can talk, they said, you can breathe. Minutes later, the boy was dead. He was 15 years old.

An inquest followed. The jury returned a devastating verdict, exposing a custodial system that was rotten from root to branch. For Mr Myatt’s mother, Ms Pam Wilton, though, it wasn’t enough to know what happened. She needed, more than anything, to know why. What was going through the heads of those officers as they held down her son? How could they not perceive his pain? She asked her lawyer, Mr Dexter Dias QC, but he could offer no explanation.

Now, more than 13 years after Mr Myatt’s death, the man who defended him in court is finally ready to provide an answer to his mother's question – the question of who we are and what we are really capable of. In his book, The Ten Types Of Human, Mr Dias introduces us to 10 mental modules, or types, that shape our thoughts and, ultimately, our actions in the most extreme circumstances. Drawing on more than 25 years’ experience as a human rights lawyer, he illustrates these types – which have names such as The Aggressor, The Nurturer and The Perceiver of Pain – using an extraordinary cast of real-life characters, from child slaves in Ghana and acid-attack survivors in Uganda to human-trafficking escapees in Kazakhstan.

In conversation with MR PORTER last week, Mr Dias explained that, while the case studies in the book may shock, the message they convey is ultimately uplifting: that by understanding how our minds work, we can learn how to be better people. “The goal,” he said, “is to reduce the sum of human suffering in the world.”

Let’s begin with the question you must get asked the most: which type am I?

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The answer is that you’re no single type. You are every type. The 10 types exist in us all (in reality, there are more than 10, but these are just the ones I’ve identified). They have evolved through natural selection to deal with the challenges faced by our ancestors. They have shaped – and continue to shape – our species.

Your book arrives at a time when the mindset of terrorists is under great scrutiny in the UK. Do the 10 types offer an explanation?

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Well, there’s an interesting combination of three different types at play. First, there’s The Ostraciser. These people often feel marginalised from mainstream society. Recent neurological experiments have shown that the social pain of rejection activates the same neural pathways as physical pain, so we’re talking about something that actually hurts here. Then there’s The Tribalist. Marginalised people desperately want to feel as if they belong to something, which makes them easy prey for radicalist groups. Finally, you have The Aggressor. Once exposed to radicalisation, they become angry, and in this vengeful, enraged state of mind, they become unable to perceive the pain of others. Put these three types together, and you have the recipe for terrorism.

So it’s got nothing to do with evil?

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Evil is the easy answer. As a concept, though, it’s simplistic. It tells us nothing about the mechanism. It fails to answer the question: what are we going to do about it? How are we going to stop this from happening again?

What is the answer, then?

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If the analysis is correct, then one of the contributory factors is social exclusion. The more we exacerbate that, the greater number of young people are going to become alienated and open to radicalisation. So, one of the most important things is social cohesion. And you don’t create social cohesion, it seems to me, through a culture of demonising certain communities – entire communities – because of the actions of a tiny percentage of those communities.

Your book is a rallying cry for moral progress. Is progress the default direction? It sometimes feels as if we’re going backwards.

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I do think that there’s the possibility of a direction of travel in terms of morality. Look at what’s happened in the past 50 years. Things are changing. Let me give you an example. A lot of the work I’ve done recently has been on FGM [female genital mutilation]; 200 million women and girls living with the scars. Another three million victims every year. That’s about one every 11 seconds. It’s an astonishing figure. But things are changing. Look at Djibouti, for example, where I’m liaising with various UN organisations. We have reduced the incidence of FGM in Djibouti from more than 95 per cent of girls down to about 78 per cent. That’s still an enormous amount, but think of the girls who have been saved.

That’s not something that happens on its own, though.

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You’re right. You have to remember the Edmund Burke quote: “The only thing necessary for the triumph of evil is for good people to do nothing.” So the question becomes: how many people want to get involved with this fight? There’s going to be a direct correlation between the number of people fighting for change and the amount of time it takes to eliminate this. But we’re going to eliminate it. It’s just a question of time because people, by and large, are good. They want to do the right thing.

The Ten Types Of Human (Penguin) by Mr Dexter Dias is out now

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