What makes you… you?
Personality isn't just about psychological attributes, such as whether you're an extrovert or an introvert, gregarious or thoughtful – it's also about our actions.
Often our 'personal projects' reveal more about us than how we behave, says author and psychology professor Brian Little.
So who are you really?
Little's 'big five' personality traits spell the acronym OCEAN – openness, conscientious, extroversion, agreeableness, and neuroticism.
"These traits help predict important aspects of our lives, how well we do in our various ventures.
"But I think that if we just look at those relatively fixed traits we miss something really important."
Little is a self-described 'classic' introvert who doesn't like too much stimuli, yet he acts like an extrovert for his students, so they'd never know this, he says.
"Many of your listeners are like this… You act of character through what I call 'free traits'.
"I act out of character as a pseudo-extrovert for some reasons which the listener may identify with."
Many of us do it out of a sense of professionalism, he says.
"There is evidence there is a genetic component to some of these relatively fixed traits, but the research … shows that we're able to override those natural tendencies and so … I can act out of character."
But there can be costs to acting out of character.
"We need what I call a 'restorative niche' … escaping to the men's room. I go to the washroom.
"There are different orientations, there are different free traits we may enact.
"To put everybody in the same box is really a mistake."
People often spend a great deal of time trying to figure out who they are, but this can be destructive and lead to rumination, he says.
Neuroticism – which Little prefers to characterise as high sensitivity – is a trait that helped humans evolve to spot threats.
Neurotics can be thought of as canaries in a coal mine, spotting something things others do not notice, he says.
"They are in contrast to extroverts … Neurotic individuals are primarily sensitive to avoiding punishments so they are very sensitive to danger cues.
"If we just dismiss them as merely neurotic we may miss that they have some function that is very valuable in our social groups."
Little says if he wants to truly understand someone he investigates their life's "core projects" – whether that's a profession, educational aspirations or an out-of-character relationship.
"In a way, the answer to who you are is what you are doing, what you plan to do, and how successfully you're able to do that."
The doing, the venturing forth, the taking a step, is really important as long as you take care of oneself, he says.
People trying to re-shape their lives may attempt to change everything, but small steps are more successful.
Professor Little explores personality and introverts in a popular TED talk,
He is also the author of Who Are You Really? The surprising puzzle of personality.