Impersonation?

It can feel like a lottery. Are you an extrovert? Congratulations! You have a greater chance of being happy. Are you conscientious? Brilliant! You have a higher life expectancy.

But people who score highly for other traits might be less lucky. Studies suggest that those with high neuroticism scores are less likely to be satisfied in relationships. Meanwhile, high levels of agreeableness are linked to lower salaries.¹

For much of history, we have tended to see personality as something we cannot change. In 1890, the psychologist William James wrote that by the age of 30 personality is "set like plaster". But given that surveys suggest that a minimum of two-thirds of people would like to change some aspect of their personality, this was not great news.

In more recent research, scientists are advising against seeing personality as a life sentence. In one 15-week trial, 400 people were tasked with shifting their personalities as judged by the Big Five test through taking on two "challenges" each week, with promising results.

A larger trial of 1,500 people came to a similar conclusion: that participants could change their personalities so much that the changes were apparent even to friends and family.

The Big Five test of personality posits five core traits: extroversion, conscientiousness, agreeableness, openness, and neuroticism. Many see the first four as desirable, since higher levels of them are linked with greater life satisfaction.

For some, the idea that character can change is a no-brainer. After all, even the word personality itself is derived from the Latin word persona, meaning "mask".

But others are more loyal to the idea of a core or even pre-determined self: William WordsworthAn English writer (1770-1850) best known for his poems about nature, such as Daffodils. wrote that "Child is the Father of the Man" - that we always move back to our childhood identity.

AristotleA student of Plato, tutor to Alexander the Great and the father of political philosophy.'s famous 2,300 year old mantra was that we become what we repeatedly do. If a knife had a soul, the act of cutting would be a part of that soul.

Meanwhile, in Buddhism, the term anatta refers to the idea of "non-self" - the idea that there is no permanent, unchanging essence, self or soul in any phenomenon in the world, including human beings.

Yes: Evidence from the studies cited shows that if we consistently adopt new habits, it is more than possible to change our personalities. Some studies also show that just one month of therapy can reduce levels of neuroticism by half of the amount it would usually decline in a lifetime.

No: We might be able to develop or reduce certain traits, but ultimately personality is much bigger than that, based on all of our life experiences and biology. That cannot be changed.

Or... Changing your character probably gets harder with age. Some studies show that whilst younger people have a more flexible sense of self, when the brain stops developing your personality becomes more fixed.