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Read an extract from Be Who You Want

Read an abridged extract from Chapter One of Christian’s Jarrett’s Be Who You Want, the inspiring new guide to the science of personality change.


Like many other young men, twenty-one-year-old Femi had fallen in with the wrong crowd. In 2011, when police pulled him over for speed­ing through northwest London in his Mercedes, they found 8 oz. of cannabis in his sports bag. He was charged with possession of drugs with the intent to supply.

If you’d encountered Femi back then, you might well have con­cluded that his was the kind of disagreeable personality you’d rather avoid. After all, the drug arrest wasn’t his first brush with the law; it was part of a pattern of behaviour that led him to be ordered to wear an elec­tronic tag. He was often in trouble in his younger years. “I got banned from the area I was growing up in because I was getting into too much trouble,” he recalls.

However, Femi, or to use his full name, Anthony Oluwafemi Olan­seni Joshua OBE, became an Olympic gold medalist and a two-time heavyweight boxing champion of the world, heralded as an impeccable role model of clean living and good manners. “He really is one of the nicest, most down-to-earth young men whose acquaintance you’ll ever make,” wrote Michael Eboda, chief executive of Powerful Media, pub­lisher of the Powerlist (an annual listing of the most influential Black people in Britain), in 2017. “I could have gone the other way, but I choose to be respectful,” Joshua said in 2018 as he laid out his plans to help educate the next generation in “healthy living, discipline, hard work, respect for all races and religions”.

People can change, often profoundly. They are one kind of per­son in one chapter in their lives, but fast-forward to later in their story and they’ve transformed into a different character altogether. And evidence for change doesn’t just come from tales of redemption or disgrace. Look around and you’ll see examples of less sensational but still surprising change that are everywhere. As a child, Emily Stone was so anxious and prone to such frequent panic attacks that her par­ents sought the help of a psychotherapist. “My anxiety was constant,” she told Rolling Stone magazine. “At a certain point, I couldn’t go to friends’ houses anymore – I could barely get out the door to school.” It’s hard to believe that this girl would not only overcome her nervous dis­position but that as Emma Stone (the name she chose when she joined the Screen Actors Guild), she would become the world’s highest-paid actress, decorated with an Oscar, Golden Globes and a British Acad­emy of Film and Television Arts award.

I’ve been struck by how often people have stories like this to tell and how their trans­formations are consistent with and explained by, the findings com­ing out of the exciting new psychology of personality change. Radio phone-ins, online chat forums and glossy magazine pages are filled regularly with stories of change, often for the better: lazy people find­ing purpose, shy people discovering their voice, criminal offenders turning good.

Learning these lessons from the science of personality change is arguably more important today than ever before. The pandemic has shaken all our lives, testing our adaptability. Sources of distraction, from social media to smartphone games and apps, are more ubiquitous, draining our focus and self-discipline. Outrage and political polarisation are everywhere as people get sucked into Twitter pile-ons and political discourse plumbs new lows, draining civility. Sedentary lifestyles are also on the increase, which research shows has damaging effects on personality traits, weakening determination and fermenting negative emotions. Yet the inspiring tales of positive personality change show you don’t have to submit to these harmful in­fluences passively; it’s possible to take the initiative and shape your own character for the better.

The fact that we are capable of change does not mean we should entirely dismiss the concept of personality. Far from it. According to decades of careful psychological research, there is such a thing as “personality” – a relatively stable inclination to act, think and relate to others in a characteristic way. This includes whether we seek out social company and how much we like to spend time deep in thought. It reflects our moti­vations, such as how much we care about helping others or being suc­cessful; and it’s also related to our emotions, including whether we tend to be calm or prone to angst. In turn, our typical patterns of thought and emotion influence how we behave. Combined, this constellation of thoughts, emotion and behaviour forms your “me-ness” – essentially, the kind of person you are.

When it comes to defining and measuring personality, a problem for psychologists has been the vast number of possible character la­bels available, some more flattering than others: vain, chatty, boring, charming, narcissistic, shy, impulsive, nerdy, fussy, arty, to name just a handful. Thankfully, modern psychology has weeded out all the redundancy in these de­scriptions, distilling the variation in human character into five main traits:

  • Extraversion refers to how receptive you are at a fundamental level to ex­periencing positive emotions, as well as how sociable, energetic and active you are. In turn, this affects how much you enjoy seeking out excitement and company. If you like parties, extreme sports and travel, you most likely score high on this trait.
  • Neuroticism describes your sensitivity to negative emotion and your levels of emotional instability. If you worry a lot, if social slights hurt you, if you rumi­nate about past failures and fret about upcoming challenges, you probably score high on this trait.
  • Conscientiousness is about your willpower – how organised and self-disciplined you are, as well as your industriousness. If you like your house to be tidy, you hate being late and you’re ambitious, you’re probably a high scorer here.
  • Agreeability refers to how warm and friendly you are. If you’re patient and forgiving and your first reflex is to like and trust new people you meet, you’re probably highly agreeable.
  • Openness is about how receptive you are to new ideas, activities, cultures and places. If you dislike opera, films with subtitles and breaking your routine, you’re probably a low scorer.

Most psychologists believe these five traits don’t fully capture the darker sides of human nature. To measure these, they propose three more – narcissism, Machiavellianism and psychopathy (known collec­tively as the dark triad).

Personality can seem a bit woolly and purely descriptive, but it’s reflected in your biological makeup, even down to the ways your brain is structured and functions. For instance, introverts don’t just prefer peace and quiet; their brains respond more sensitively to loud noises. Neurotic folk don’t just experience more mood swings; they also have less surface area and folding in the parts of their cerebral cortex that are responsible for regulating emotions. In the front of their brains, people with more advantageous personality traits – such as greater resilience and conscientiousness – have more my­elination, the insulation around brain cells that helps them communi­cate efficiently. Personality traits are even related to the microbiome in your stomach, with neurotic people having more harmful gut bacte­ria.

So personality is a genuine concept with biological underpinnings. Yet as the earlier stories imply, personality is not set in stone – or plaster, for that matter. That was the metaphor pre­ferred by the great American psychologist William James in the nineteenth century, who observed in his Principles of Psychology that by age thirty, our personalities are set in plaster and our capacity for change is over.

In fact, there’s a sense in which your capacity for change is more ap­parent beyond age thirty. It’s notable that whereas the genetic influences on cognition – things like your intelligence and memory abilities – in­crease through life, the genetic influences on personality decline, argu­ably reflecting the increasing scope for life events and other experiences to leave their mark, like new jobs, relationships or moving abroad.

Humans have evolved to be adaptable. You can think of your cur­rent personality traits as the behavioural and emotional strategy that you’ve settled on to best survive and thrive in the circumstances you find yourself in. Your genetic disposition makes it more likely that you might settle on some strategies more than others, but it doesn’t confine you to one approach to life and relationships and you are not stuck with your current way of being.

It’s true that personality tends to become more stable with increas­ing age, but this isn’t because of a lost capacity for change. It’s because most people’s circumstances become progressively less varied as they settle into the grooves of adult life.

Zoom out and it’s clear that most of us change throughout life. If you follow the typical pattern, you’ll become friendlier, more self-disciplined and have less angst as you get older. Occasionally the big choices you make in life – the career paths you take, the relationships you form – will bring about more profound changes. The effect of major events like graduation, parenthood, divorce, bereavement, illness and unemployment also accumulate. The longest-ever personality study, published in 2016, involved a comparison of participants’ personalities at age fourteen and then again at age seventy-seven and it failed to find much correlation between the two times.

Of course you also show trait-like changes in your behaviour over the short term, in response to things like your mood, the people you’re with (think how you act around your boss or grandmother compared with your best friend, for instance), or what you’ve had to drink. Consider how tennis star Rafael Nadal’s persona on and off court are said to be so different that it’s like Superman and Clark Kent. His mother “never ceases to be amazed by how brave he is on the tennis court and how fear-ridden off it”.

Your personality traits make you who you are and shape the life you will lead, so this idea that they are to some extent constantly evolving and readily moulded by life may seem unsettling. But it’s also an empower­ing revelation. By familiarising ourselves with the ways that our person­alities shift and bend at different life stages and in response to different circumstances, we can anticipate and exploit our capacity for change. More than that, we don’t have to be passive observers, waiting for events to shape us. Inspiring new research shows that with the right attitude, enough dedication and suitable techniques, we can literally choose to change our personalities at will, to be who we want through outside-in ap­proaches – placing yourself in the right situations, choosing carefully whom you spend your time with and taking up new hobbies and mean­ingful projects – and inside out, through mental and physical exercises and altering your habits of thought and emotion. After all, your person­ality arises from your style of thought, motivations, emotions and habits. Address these and you will change yourself and your life.