From eccentric and introverted to boisterous and bold, the human personality is a complex and colorful thing. Personality refers to a person’s distinctive patterns of thinking, feeling, and behaving. It derives from a mix of innate dispositions and inclinations along with environmental factors and experiences. Although personality can change over a lifetime, one’s core personality traits tend to remain relatively consistent during adulthood.

While there are countless characteristics that combine in an almost infinite number of ways, people have been trying to find a way to classify personalities ever since Hippocrates and the ancient Greeks proposed four basic temperaments. Today, psychologists often describe personality in terms of five basic traits. The so-called Big Five are openness to experience, conscientiousness, extraversion, agreeableness, and neuroticism. A newer model, called HEXACO, incorporates honesty-humility as a sixth key trait.

What’s My Personality Type?

The idea of a personality “type” is fairly widespread. Many people associate a “Type A” personality with a more organized, rigid, competitive, and anxious person, for example. Yet there’s little empirical support for the idea. The personality types supplied by the popular Myers-Briggs Type Indicator (MBTI) have also been challenged by scientists.

Psychologists who study personality believe such typologies are generally too simplistic to account for the ways people differ. Instead, they tend to rely on frameworks like the Big Five model of trait dimensions. In the Big Five model, each individual falls somewhere on a continuum for each trait—compared to the rest of the population, a person may rate relatively high or low on a trait such as extraversion or agreeableness, or on more specific facets of each (such as assertiveness or compassion). The combination of these varying trait levels describes one’s personality.

To assess these individual differences, a variety of personality tests have been created. These tests commonly prompt people to indicate the extent to which various descriptions of thinking or behavior reflect their own tendencies. Based on a person’s responses, the test yields a “personality type” description (in the case of a test like the MBTI) or indicates how one compares to other respondents on a number of traits (in the case of the Big Five Inventory or similar measures).

Personality Traits

Traits are the building blocks of personality. So what is a trait? In short, it’s a relatively stable way of thinking and behaving that can be used to describe a person and compare and contrast that person with others.

Traits can be cast in very broad terms, such as how positively disposed a person generally is toward other people, or in more specific ones, such as how much that person tends to trust other people. These more specific aspects of personality are sometimes referred to as “facets.” Personality traits are usually considered distinct from mental abilities (including general intelligence) that are assessed based on how well one responds to problems or questions.

Psychologists have developed a variety of ways to define and organize the span of personality traits. They are often bundled together based on broad personality factors, as in the commonly used Big Five trait taxonomy. But personality can be sliced in many different ways, and some traits are frequently measured and studied by psychologists on their own.

Here are some of the scientifically studied groups of personality traits. Importantly, people generally do not simply have these traits or not have them—they can rate high, low, or somewhere in the middle on each one, compared to other people.

The Big Five Personality Traits

The Big Five traits—usually labeled openness, conscientiousness, extroversion, agreeableness, and neuroticism, or OCEAN for short—are among the most commonly studied in psychology. The five-factor model splits personality into five broad traits that an individual can rate higher or lower on compared to other people, based on the extent to which the person exhibits them. Each of the five personality factors covers a group of narrower personality facets that tend to go together in individuals.

What is openness?

Openness (also called openness-to-experience or open-mindedness) reflects, roughly, how receptive a person is to new ideas and the robustness and complexity of a person’s mental life. Facets include intellectual curiosity and creative imagination.

What is conscientiousness?

Conscientiousnessis a person’s tendency to control impulses and act responsibly and productively. It may be reflected in a person’s preference for keeping things in order, dependability at work, or punctuality. Grit, a much-talked-about trait concept involving steady persistence toward a goal, is related to conscientiousness.

What is extroversion?

Extroversion can be thought of as the level of energy with which a person interacts with the outside world and other people. Aspects of extroversion are thought to include sociability and assertiveness, but also one’s general energy and enthusiasm. Introversionis the opposite of extroversion. (Shyness, not included in the Big Five, is similar, but not the same as introversion.)

What is agreeableness?

Agreeablenessis a person’s degree of positivity and helpfulness toward other people. Facets of agreeableness include one’s respectfulness toward others, compassion, altruism, and tendency to trust others.

What is neuroticism?

Neuroticism (sometimes called negative emotionality) is a person’s disposition to experience challenging emotional states such as anxiety and depression. Highly neurotic people tend to feel negative emotions more easily; the opposite of neuroticism is sometimes described as “emotional stability.”

HEXACO and Honesty-Humility

Some personality researchers have proposed a sixth major trait factor, in addition to the Big Five: it’s called honesty-humility and provides the “H” in the HEXACO model. Honesty-humility as a trait concept reflects the degree to which people place themselves ahead of other people, such as by seeking special treatment or manipulating others. Proposed facets include sincerity, fairness, and the avoidance of greed.

The Dark Triad

Three traits, often called the Dark Triad—narcissism, psychopathy, and Machiavellianism—are commonly assessed to investigate the darker, or more antagonistic and self-interested side of human nature. While they represent particular ways of thinking about anti-social thoughts and behavior, they are not necessarily separate from other traits—for instance, it’s easy to see how they share some common ground with the Big Five concept of agreeableness or HEXACO’s honesty-humility.

Some people who rate highly on these traits are described as being “a narcissist” or a “psychopath,” but the Dark Triad traits can be thought of in terms of a spectrum: A person can rate low, high, or anywhere in between on each one. Personality disorders, some of which involve Dark Triad-related behavior, are defined differently, using specified cut-offs for diagnosis.

What is narcissism?

Narcissism is generally one’s sense of self-importance and entitlement relative to others. High narcissism may be reflected in attention-seeking or an excessive need for admiration.

What is psychopathy?

Psychopathy captures a lack of empathy, remorse, and impulse control, along with other specific facets. Someone who is highly psychopathic may tend to hurt others without feeling bad or taking responsibility.

What is Machiavellianism?

Machiavellianism refers to a person’s tendency to treat others in a calculating way, including using manipulation in order to achieve goals. It is named after Niccolò Machiavell, the 16th-century author of the book The Prince.

Personality Tests

The psychology of personality promises to help people better understand themselves and those they know in relation to others. Personality tests, which typically take the form of questionnaires, are the tools for doing that. These measures of personality are also used in scientific research to explore how individual differences in various traits correspond with other aspects of people’s lives.

Personality tests are only “tests” in a loose sense: There is no right or wrong answer to their questions. And the best personality measures are not “pass/fail”—they don’t sort individuals into one category or another, but instead place them on a series of trait continuums depending on how they compare to other people.

How Valid Personality Tests Work

There are countless personality tests. Even a well-established set of traits like the Big Five can be assessed using a number of different questionnaires. Still, scientifically validated personality tests tend to have some features in common.

Test-takers typically read a series of items that describe a person and indicate the degree to which the description applies to them—or another person, if they are rating someone else’s personality. These lists can be as short as 10 items and as long as a couple of hundred (longer tests tend to provide more reliable results), and the items can be single adjectives or full statements about one’s nature.

For example, the second version of the Big Five Inventory includes the following statements, along with several dozen others, each of which is used to assess one of the Big Five traits:

• Is complex, a deep thinker. (openness)
• Is reliable, can always be counted on. (conscientiousness)
• Is talkative. (extroversion)
• Is compassionate, has a soft heart. (agreeableness)
• Keeps their emotions under control. (emotional stability/neuroticism)

When the ratings for the various items are totaled, the scores allow for comparisons between the individual and average scores based on samples of other test-takers. In this way, one can find out that they rate above average on openness, conscientiousness, and agreeableness, low on extroversion, and high on neuroticism—or any other mixture of trait evaluations.

While Big Five tests like the BFI-2 are relatively comprehensive, providing a broad picture of a person’s personality, there are many other questionnaires, some of which (such as the Narcissistic Personality Inventory) focus on a specific trait. Other personality measures, like the Hare Psychopathy Checklist, are administered through an interview with a trained professional, rather than with a self-test.

Widely Used Personality Tests

Below are some of the most well-known and commonly used tools for assessing personality. Many are referred to as “inventories,” reflecting a collection of items to which a person responds, each one tied to different dimensions of personality. These measurement instruments are used in a range of contexts, from psychology studies to employee evaluation, and—importantly—some are better supported than others by scientific research.

• Big Five Inventory-2 (BFI-2) is the latest version of a tool for assessing the Big Five personality traits, which it labels as Extroversion, Agreeableness, Conscientiousness, Negative Emotionality, and Open-Mindedness, as well as facets of each. It is employed in psychological research and can be used for personal assessment.
• The Revised NEO Personality Inventory (NEO PI-R) is a revised version of a tool originally named after the Big Five trait factors of Neuroticism, Extroversion, and Openness to Experience, though the current tool assesses Agreeableness and Conscientiousness as well, plus 30 more specific traits within each factor. It is used in psychological research.
• The HEXACO Personality Inventory-Revised (HEXACO-PI-R) is used to measure six dimensions of personality, based on the HEXACO model. They include factors that correspond to the Big Five, as well as the factor of Honesty–Humility. It is employed in psychological research and can be used for personal assessment.
• The Minnesota Multiphasic Personality Inventory (MMPI) is used primarily to assess symptoms of mental illness and maladaptive personality traits. The latest version (MMPI-2-RF) includes scales related to aggression, social avoidance, self-doubt, and other specific problems, as well as scales for broader, overarching factors. The MMPI is used for research and in applications such as mental health care, forensic evaluation, and candidate assessment for public safety jobs.
• The Hare Psychopathy Checklist-Revised (PCL-R) is an instrument designed to measure psychopathic traits, such as impulsivity and lack of remorse or guilt, in criminal offenders or others in forensic settings. Unlike personality tests that involve self-report questionnaires, it is meant to be administered through an interview and evaluation of the individual by a clinical professional.
• Psychopathic Personality Inventory-Revised (PPI-R), like the Hare checklist, is designed to assess a person’s levels of psychopathic traits, but it was developed for use with non-criminals and its results are based on responses to questionnaire items.
• The Narcissistic Personality Inventory (NPI) is used to specifically assess an individual’s level of narcissism, often in a research context, though it can also be used for self-evaluation. It is not used for diagnosis of Narcissistic Personality Disorder, which is based on criteria in the DSM-V.
• The Hogan Personality Inventory (HPI) is based on the five-factor model and intended for predicting work performance, including in job candidates. Its scales are organized based on work-relevant characteristics such as ambition, sociability, and interpersonal sensitivity.
• The Myers Briggs Type Indicator (MBTI) assigns individuals a psychological “type” summarized in four of eight possible letters: Extroversion (E) or Introversion (I); Sensing (S) or Intuiting (N); Thinking (T) or Feeling (F); and Judging (J) or Perceiving (P). The results combine into one of 16 types, such as ENTJ or ISFP. The MBTI is widely used in business—such as for employee evaluation or during seminars—and unofficial versions are available for personal use, though scientists often cite its limitations, including that its separate “types” oversimplify personality differences.
• DISC or DiSC is the name given to a collection of personality assessments that assign individuals one of four types, or a blend of the types: Dominance (D), Influence (I), Steadiness (S), and Conscientiousness (C). Like the Myers-Briggs, it is promoted for use in learning about individual differences within organizations, but is generally not favored by contemporary personality scientists.
• Enneagram-related tests are based on the concept of the Enneagram of Personality and assign personality descriptions based on nine primary types and often secondary types called “wings.” While the Enneagram has been promoted in business and spiritual contexts, it lacks empirical support and is infrequently used by personality scientists.

Which personality tests are best?

Any personality test can be fun and intriguing. But from a scientific perspective, tools such as the Big Five Inventory (and others based on the five-factor model) and those used by psychological scientists, such as the MMPI, are likely to provide the most reliable and valid results. One thing that sets many of these tests apart is more nuanced scoring. The Myers-Briggs and other tests are used to assign people personality “types,” but traits are not black-or-white: the research suggests that they are more like a spectrum, with high and low ends.

Are there any perfect personality tests?

While measures of the five (or six) proposed personality factors offer a relatively comprehensive and nuanced view of personality, they have limitations, too. Research suggests they may provide less reliable results outside of Western, industrialized countries—and that the major factors may not manifest in the same way everywhere in the world.

How can I obtain a personality test?

That depends on the test. Some, like the Big Five Inventory, can be taken online. Others, like the NEO Personality Inventory or the Myers-Briggs, must be acquired from a publisher for a fee—though brief or adapted versions of such tests may be available online.

How do I know whether an online test is valid?

In addition to the above descriptions of each kind of test, consider the source of any online test. A test provided directly by a scientist at a well-known university may be more empirically supported and informative than one offered by someone with no scientific credentials. Tests that provided nuanced scores (in terms of percentiles, for example) are likely to be more valid than those that give you a specific “type.”

Personality psychology—with its different ways of organizing, measuring, and understanding individual differences—can help people better grasp and articulate what they are like and how they compare to others. But the details of personality are relevant to more than just a person’s self-image.

Why Personality Matters

The tendencies in thinking and behaving that concepts like the Big Five represent are related to a variety of other characteristics and outcomes on which people compare to one another. These include differences in personal success, health and well-being, and how people get along with others. Even the risk of dying appears to be associated to some degree with differences in personality traits.

Personality also crosses into the realm of mental health: Professionals use a list of personality disorders involving long-term dysfunctional tendencies to diagnose and treat patients. Among the categories used by psychiatrists and clinical psychologists are the commonly discussed narcissistic personality disorder, borderline personality disorder, and antisocial personality disorder—but a major diagnostic guide, the DSM, includes 10 personality disorders in total.

Personality and Life Outcomes

If personality traits truly set individuals apart in meaningful ways, then they should also be related to other differences between people—including how they fare in life, for better or worse. And that is exactly what scientists who study personality have found.

Each major personality factor examined by psychologists has been linked to one or more outcomes of interest, from measures of achievement to mental health to satisfaction in romantic relationships. This suggests that personality matters in a broad way. The associations between personality differences and life outcomes only show general tendencies: While very extroverted people report higher well-being than very introverted people, on average, there are countless happy introverts. But the findings do, on the whole, reveal something about the experiences and challenges that people with certain personalities tend to face.

Do personality traits actually cause greater success or rockier relationships, or do traits and outcomes all stem from some shared, underlying factors? It’s difficult to determine how much personality itself is responsible for our ups and downs, though there is reason to believe that traits do have some impact on the important domains of our lives with which they are linked.

Personality, Well-Being, and Health

Both mental and physical health are related to differences in personality. From how happy people are with their lives at any given point to matters of life and death, people who rate higher on some personality traits and lower on others appear to be in better shape.

What are the links between personality and happiness?

On measures of psychological well-being, people higher in extroversion and conscientiousness tend to rate better, while those higher in neuroticism rate worse. Here, as in other domains, the positive outcomes of people with certain traits—in this case, the highly extroverted and conscientious—may relate in part to the positive situations (such as rewarding social encounters) that these people are likely to create for themselves.

Do people with certain personalities live longer?

Personality traits have been linked to health risk and life expectancy. Research finds that people who are higher in conscientiousness, extroversion, and agreeableness face a lower risk of dying, on average, while people high in neuroticism are at greater risk overall. Evidence suggests the increased risk of smoking among more neurotic people plays a small role.

Are the links between personality and well-being the same everywhere?

They may not be. For example, the link between extroversion and well-being could be limited to certain cultures, including those of North America. Similarly, one investigation found that the relationship between low extroversion and mortality was stronger in the U.S. than in other countries.

Personality and Relationships

Individuals spend much of their lives in relationships, and personality traits such as extroversion and agreeableness are highly socially relevant. So it’s sensible that how well people get along with romantic partners may depend, in part, on their distinct personality features. Research supports the idea that some traits correspond with higher-quality relationships.

How are the Big Five traits associated with relationships?

• One of the traits most relevant to social life is extroversion: More extroverted participants in studies have rated higher on measures of social success, such as self-perceived status and acceptance of peers. Higher extroversion, conscientiousness, and agreeableness also seem to correspond with somewhat greater satisfaction in romantic relationships, on average. Neuroticism has been linked to poorer romantic outcomes. 

How are attachment styles linked to relationship satisfaction?

Attachment styles, which can also be thought of as elements of one’s personality, have also been connected with relationship outcomes. Research suggests that those who are “insecure” in their attachments—who exhibit high anxiety or avoidance related to close relationships—tend to be less satisfied with their relationships.

How else do traits relate to good or bad social outcomes?

Some people—such as those high on the “dark” personality constructs of psychopathy or narcissism, or those with a personality disorder—are especially prone to behave in ways that cause harm to others, potentially undermining or destabilizing their relationships. At the level of Big Five traits, studies suggest that low conscientiousness is correlated with a tendency toward antisocial behavior. High agreeableness, meanwhile, has been linked to the more benign tendencies to forgive and to experience gratitude.

Personality and Success

Beyond the likelihood of living a long life and finding romantic satisfaction, personality traits appear to be relevant to more conventional forms of achievement. From grades, to career interests, to income, science has uncovered associations between how individuals’ traits and successes stack up.

Do people with certain personalities make more money?

• If success is to be measured in dollars and cents, people who rate highly on certain traits seem to have the overall advantage. Research has connected high agreeableness with lower earnings and high conscientiousness with greater earnings. However, one’s line of work undoubtedly matters: certain jobs may call for more or less extroversion, conscientiousness, openness to experience, or other traits, and a closer match to the job’s demands may spell greater success. 

How is personality related to a person’s work?

Extroverted study participants have exhibited stronger tendencies toward leadership and higher occupational commitment, on average, while those higher in neuroticism seem to have somewhat lower commitment. Personality may also shape a person’s career interests. People higher in openness, for example, have shown a stronger inclination toward artistic occupations.

What else does personality relate to?

Personality is enmeshed enough in people’s lives that many other ties between traits and psychological measures have been identified—although the size of some of the correlations is modest. To give just a few examples, associations have been found between lower openness and TV viewing; lower agreeableness and criminal behavior; and higher extroversion and volunteerism.

Judging Personality

Everyone has a distinctive personality, and human beings start trying to get a read on each other immediately. These first impressions may not be completely accurate—but personality differences do have links to outward behavior and even appearances, which can provide early hints about what an individual is generally like. Over time, witnessing how a person tends to think and act in different situations will likely provide a better picture of the person’s traits.

Do first impressions accurately reflect a person’s personality?

To an extent, they can. Some research suggests that even based on a photograph of someone, people’s judgments—while far from perfect—accord with those of the individual to a significant degree for some traits, including extroversion.

How is personality related to appearance?

Dress, facial expression, and other visible details may offer signals of personality. Smiling and looking energetic might be signs that a person is relatively extroverted, for instance. Looking healthy and relaxed may indicate emotional stability. Some researchers even report that distinctive eyebrows may provide a signal of grandiose narcissism. Psychologists have also found evidence that the condition of one’s surroundings is associated to some degree with personality traits. For instance, having an organized bedroom was associated with conscientiousness, while displaying varied books was linked to greater openness to experience.

Are some personality traits easier to judge than others?

Some personality researchers have suggested that personality traits with more visible signs in outward behavior should be easier to judge. A person’s level of extroversion is associated with social engagement and may be more effectively gauged by outsiders than a trait such as neuroticism, which includes tendencies toward anxiety and depression.

What is the halo effect?

The halo effect is a bias in which a person who has one desirable characteristic, such as physical attractiveness, is more likely to be viewed as having other favorable characteristics. Research suggests this can extend to perceptions of certain personality traits, such as conscientiousness or kindness.

Personality Disorders

Personality Disorders are long-standing patterns of thinking and behavior that lead to problems in interpersonal relationships and may cause impairment or distress in the person with the disorder.

A personality disorder may reflect a potentially disruptive combination of personality traits, such as low agreeableness or high narcissism, that make it more difficult for someone to get along smoothly with others in life or dispose the person to treat others poorly. In practice, however, personality disorders are typically defined in terms of sets of signs and symptoms that reflect the harm or difficulty stemming from a person’s way of being.

The Diagnostic and Statistical Manual of Mental Disorders includes 10 personality disorders, grouped into three clusters.

Cluster A: Paranoid, Schizoid, and Schizotypal Personality Disorders

Cluster A personality disorders are characterized by odd or eccentric patterns of thinking. These may include persistent suspiciousness of or disinterest in other people or strange beliefs that are not better attributed to a psychotic disorder such as schizophrenia.

What is Paranoid Personality Disorder?

Paranoid Personality Disorder involves a distrust of other people in various areas of one’s life. Potential signs include irrational suspicions that one is being manipulated by others, that others are untrustworthy, or that others are communicating hidden threats or insults.

What is Schizoid Personality Disorder?

Schizoid Personality Disorder is a pattern of detachment from social relationships in general and limited emotional expression in social settings. It may involve a lack of desire for close relationships, an overwhelming preference for solitude, or a lack of apparent concern about others’ praise or criticism.

What is Schizotypal Personality Disorder?

Schizotypal Personality Disorder involves a discomfort with and limited capacity for having close relationships along with cognitive or perceptual abnormalities—which may include magical beliefs (such as in telepathy) that influence behavior, false beliefs that events are directly related to them, or social anxiety due to paranoid fears.

Cluster B: Antisocial, Borderline, Histrionic, and Narcissistic Personality Disorders

Cluster B personality disorders are marked by unstable emotional states and erratic behavior. For those with such disorders, the propensity to lash out or to try to manipulate others, along with other behaviors, can cause major disruption in interpersonal relationships.

What is Antisocial Personality Disorder?

Antisocial Personality Disorder is a pattern of disregard for others’ rights, which can show up in behaviors such as repeated criminal activity, fighting, or lying, a tendency to act impulsively and failure to plan ahead, and a lack of remorse. Psychopathy and sociopathy, while not defined in exactly the same way, are related personality concepts.

What is Borderline Personality Disorder?

Borderline Personality Disorder is defined by instability in a person’s relationships, sense of self, and emotional state, as well as impulsivity (such as in risky sexual behavior or drug use). People with this disorder may have a history of troubled relationships and swing between extreme positive and negative views of other people.

What is Histrionic Personality Disorder?

Histrionic Personality Disorder is marked by excessive attention-seeking and emotional expression. This may involve inappropriate, provocative behavior, theatricality, and a discomfort with not being the focus of attention.

What is Narcissistic Personality Disorder?

Someone with Narcissistic Personality Disorder shows, in a variety of areas of life, a grandiose sense of self and need for admiration, along with a lack of empathy. It may involve arrogant behavior, exploitativeness, and a belief that one deserves special treatment. Though defined differently, it is related to the personality trait of narcissism.

Cluster C: Avoidant, Dependent, and Obsessive-Compulsive Personality Disorders

Cluster C personality disorders involve ingrained ways of thinking and relating to others that are colored by anxiety and fear.

What is Avoidant Personality Disorder?

Someone with Avoidant Personality Disorder tends to resist getting close to other people (which can include romantic partners) and fears the negative evaluations of others. The potential for rejection or embarrassment and perceived inadequacy may be frequent concerns.

What is Dependent Personality Disorder?

Dependent Personality Disorder involves an excessive need to be taken care of by others—to have others make decisions or assume responsibility, for example—that leads to fear of separation. Someone with this disorder may struggle to disagree with a partner or act in a submissive way so as not to jeopardize a relationship.

What is Obsessive-Compulsive Personality Disorder?

Obsessive-Compulsive Personality Disorder is marked by perfectionism and a demand for order and control, which can manifest in a counterproductive fixation on rules and details and a devotion to work that crowds out other parts of one’s life. It is distinct from obsessive-compulsive disorder, which is not a personality disorder.

Where Does Personality Come From?

Why individuals develop the personalities they do and how much someone’s personality typically changes over time are some of the biggest questions in personality psychology. Science provides some answers, but there is still plenty of room for debate and exploration.

Genetics partly helps to account for differences in personality traits, but other influences certainly play a role. A range of theories of personality have been proposed to explain what personality is and why individuals become who they are, with some focusing more heavily than others on potential non-genetic factors, such as a person’s taking on new social roles (like spouse or parent).

Despite its day-to-day stability, personality can change in the long term, potentially to a substantial degree over the course of a person’s life. Research suggests that people tend to show signs of increasing maturity (including, for instance, increased social sensitivity) in their personality test scores as they grow older. It may even be possible to deliberately change aspects of one’s own personality by making a repeated effort to behave differently.

Theories of Personality

From Aristotle to Sigmund Freud and Abraham Maslow, countless theories and concepts for understanding personality have been proposed. Throughout history, these and other great minds sought to answer questions not only about what personality is and how best to describe it, but also what causes personality differences, including those that make people more or less functional and resilient.

Some theories are still being tested, while others have fallen out of favor. Some compete while others complement one another. A look at some major ideas in personality psychology, both historical and recent, offers a sense of the many ways to think and talk about this complex subject.

Five-Factor Theory: Personality Is Based on Biology

Using the Big Five traits (or five-factor model) as a foundation, Five-Factor Theory proposes that the development of common personality traits is largely determined by biological factors, especially genetics. This view was inspired in part by research indicating that ratings on measures of personality are influenced by one’s genes and that other, non-genetic developmental factors (such as adoptive parents) seem to play a surprisingly small role.

The theory’s creators distinguish enduring personality traits from “characteristic adaptations,” such as attitudes or strivings, that are shaped by one’s innate disposition as well as external forces.

Who created Five-Factor Theory?

The theory was first proposed in the 1990s by psychologists Robert McCrae and Paul Costa Jr. McCrae and Costa also created the NEO Personality Inventory in the 1970s

What is the difference between Five-Factor Theory and the Five-Factor Model?

Though they have similar names, the model (which is embraced by many researchers) is a way of describing how personality traits are organized—that is, into the Big Five personality dimensions. The theory is a way of explaining how personality traits develop and change. 

Social Investment Theory: Biology and Experience Shape Personality

While personality traits are clearly related to genetics, one’s inheritance does not account for all personality differences. The environmental influences shared by siblings, such as a certain kind of parenting or childhood household, appear to play a minor part. Other factors, potentially many, must be at work.

One view, sometimes called Social Investment Theory, proposes that individuals’ personal investment in new social roles, such as by becoming a spouse or starting a job, helps explain personality development and change over time. In new roles, people are exposed to costs and benefits of behaving in certain ways, potentially shifting a person’s way of being over time—even given that the person’s personality is influenced by genetics.

Who created Social Investment Theory?

Multiple researchers have helped develop it. One proponent is psychologist Brent Roberts, who with colleagues in the ’00s, wrote about a “social investment principle.” (They have also called their concept the Neo-Socioanalytic Model.)

What kinds of social roles might lead to personality change?

In a new job, one may be rewarded for being punctual and putting in work to complete tasks, or incentivized to get along with others. Interpersonal or familial roles, such as being in a new relationship, may also affect personality traits.

Can personality lead us to pick certain roles?

Yes: The social investment view suggests that people with certain traits will be more drawn to and more likely to invest in certain kinds of roles. The experience of inhabiting those roles may in turn influence their personality, potentially by reinforcing existing tendencies—for example, a conscientious person might choose a career that ultimately makes her more conscientious. 

Cognitive-Affective Theory: Personality and Situations

Even someone who shows certain tendencies—to act aggressively or passively compared to others, for example—won’t necessarily behave the same way in every situation or kind of social interaction. (The authority of the person one confronts, or whether one is in public, may make a difference.) Some personality theorists have sought to weave situational factors into how personality is conceived.

In one theory, the cognitive-affective personality system (CAPS), “cognitive-affective mediating units” are thought to interact with each other and with the characteristics of different situations to produce the patterns of behavior that distinguish individuals. These “units” may include psychological factors such as an individuals’ expectations and beliefs, goals and values, and emotional responses.

Who proposed the cognitive-affective personality system (CAPS)?

CAPS was developed by psychologists Walter Mischel and Yuichi Shoda in the 1990s. They sought to resolve an apparent conflict between findings of both a level of consistency in individual characteristics and variability in behavior across different situations.

Does the impact of situations mean that traits aren’t real?

No. A person may be more aggressive, reserved, or energetic in some situations and less so in others. But across many different situations, the person may still tend to be, generally speaking, more or less aggressive, reserved, or energetic than other people are.

Narrative Identity: Personality as a Story

While traits are widely accepted as fundamental to personality, theorists often combine them with other elements as part of a multi-level view. Narrative identity is one of these elements. In short, some propose that the particular narrative details of a person’s important life experiences—and how the person relates them to each other and derives meaning from them—fills out the complex portrait of who one is compared to others. While each person’s self-composed life story contains countless pieces of information, researchers have tried to identify common factors that differentiate these narratives.

Who developed the concept of narrative identity?

The psychologist most associated with narrative identity is Dan McAdams. In the 1990s, he developed a view of personality in which three levels coexisted: dispositional traits relevant to general tendencies; how one deals with challenges and tasks in specific contexts; and an identity based on stories about the self.

What are some of the factors that distinguish people’s life stories?

In a recent study, proponents of the narrative identity view offered evidence for a tentative “Big Three” factors: autobiographical reasoning, or change in one’s understanding of one’s self or past; structural aspects, including overall coherence of the life story; and motivational and affective themes, encompassing aspects like positive or negativity and sense of agency.

Psychodynamic Theories: Personality, Inner Conflicts, and Early Life

In contrast to modern trait theories, those rooted in psychoanalytic ideas have tended to emphasize the potential role of early development in shaping personality. Sigmund Freud, the father of psychoanalysis, described personality, in part, as comprising three components: the instinct-driven “id,” the morality-bound “super-ego,” and the relatively temperate “ego.” The interactions between these elements were proposed to help explain an individual’s behavior. He also believed that childhood experiences have a major impact on a person’s personality.

Many theorists who followed Freud (and whose thinking is often described using the term psychodynamic rather than psychoanalytic) refined or branched out from his ideas. One of them was Carl Jung, who proposed psychological “types” that inspired the popular test known as the Myers-Briggs Type Indicator.

Are psychoanalytic theories of personality still used?

While they have influenced popular understanding of personality, they generally lack the empirical support of contemporary theories and do not have a central place in current personality science. However, some researchers continue to work in areas informed by psychodynamic ideas—such as those who study attachment orientation and the extent to which it relates to childhood.

What are some factors that Freud thought affected personality?

Traumatic events or internal conflicts during early development were proposed as influences on personality. Identification, or adopting characteristics of someone else in one’s life, was another factor thought to play a role.

How did Freud’s followers differ from his view of personality?

Freud-inspired theorists have emphasized different proposed factors in personality formation. For example, “Neo-Freudians” such as Jung, Alfred Adler, and Karen Horney challenged Freud’s emphasis on sexual and aggressive impulses, focusing more on social and cultural factors.

Humanistic Theories: Personality and Human Potential

Humanistic psychology, developed in the mid-20th century by figures such as Abraham Maslow and Carl Rogers, focused the spotlight on individuals and their positive qualities, including their drive to achieve their full potential.

Maslow is famously known for his hierarchy of needs, with basic needs, such as nourishment and safety, toward the bottom, and self-actualization at the top. He argued that people who reach self-actualization—activating their self-perceived human potential, exhibit what he called a “coherent personality syndrome.” Rogers framed a healthy personality as the result of a match between one’s perceived self and the self one should be.

What traits did Maslow believe self-actualizers have?

Among other characteristics, Maslow proposed that self-actualized people tended to be creative, compassionate, realistic, and drawn to helping others. As he described it, self-actualization is a relatively rare achievement—he cited historical figures such as Lincoln and Einstein as examples of self-actualized people.

What other perspectives are linked to humanistic psychology?

The ideas of humanistic psychologists bear similarities to existential psychologists (such as Viktor Frankl)—theorists in both fields share an interest in the capacity of individuals to shape their own lives. Humanistic psychology also helped inspire positive psychologists, who have sought to focus attention on individuals’ character strengths and virtues.

Can Personality Change?

Almost by definition, personality traits are thought to be enduring psychological features. They mark someone as thinking and behaving in a characteristic way right now—and, probably, tomorrow and even a year from now. Indeed, research on personality development over time indicates that, at least in adulthood, individuals’ comparative ratings on traits such as extroversion, agreeableness, and conscientiousness are relatively stable.

At the same time, it’s clear that people’s personalities do gradually evolve over the lifespan, from childhood through older age, and potentially shift in conjunction with important life events, such as romantic partnerships. Individuals may even be able to change aspects of their personalities through their own volition.

While traits show stability over time, personality can indeed change—and psychologists continue to explore why, how, and when that happens.

How Personality Changes With Age

Will a kind, hard-working, and introverted teenage girl still retain those traits when she’s a 55-year-old woman? Has an outspoken and short-tempered grandfather always been that way, or has he grown more so over the years? One way to answer these questions might be: Yes and no.

Psychologists who have analyzed data on personalities taken decades apart in the lifespan find evidence for both stability and change. That is, people often resemble themselves over time rather than changing dramatically—and will likely remain more extroverted or neurotic than most if they start out that way. But there are also overall trends showing that people tend to rate higher or lower on certain traits with the passage of years.

What are some ways personality changes in adulthood?

In short, people seem to mature, or become more socially adapted, over time in ways that show up on personality tests. Personality data taken first in youth and again 50 years later showed increases in traits such as calmness (thought to be related to emotional stability) and social sensitivity (related to agreeableness). Other work has found evidence that narcissism decreases, on average, over time.

How does personality change when we’re growing up?

Children, studies suggest, may show increasingly more distinct trait profiles as they grow older. Research involving adolescents and young adults indicates fluctuations in personality over time: In the teen years, for instance, boys may become less conscientious and girls less emotionally stable, on average, with both gaining in those traits as they reach adulthood. Agreeableness also seems to increase.

Do personalities change after major life events?

They might. Some research has found an overall decline in agreeableness among newlywed husbands and wives. Husbands also exhibited lowered extroversion and greater conscientiousness, on average, and wives showed decreased openness and neuroticism. Past work has also connected first long-term relationships with decreases in aspects of neuroticism.

Changing Personality on Purpose

People can evolve over the course of experience-filled years for many different reasons. But what about the person who wants to become more conscientious or agreeable, or less neurotic or self-centered, and to do so ASAP? Recent research provides reason to be hopeful about the possibilities for intentional, self-directed personality change—though it likely requires more than just wishing to be a certain way.

Can you change your personality?

It seems possible. Several of the Big Five traits, including extroversion, conscientiousness, and agreeableness, seem amenable to volitional change—via exercises like deliberately saying hello to someone new (for extroversion)—though consistency in these efforts appeared to be important. Neuroticism (or emotional stability) is also apparently changeable, whether through special courses or through a time-worn method of change: psychotherapy.

How quickly can personality traits change?

Some interventions used to enable people to change their personalities have unfolded on the scale of months. But recent research suggests that even a two-week, smartphone-based intervention may be enough to enhance a specific facet of personality like self-discipline—at least in the short-term.

Can people with personality disorders change?

Yes. While personality disorders are thought of as long-term patterns of maladaptive thinking and behavior, there is evidence that over time, symptoms of a personality disorder can decrease—even if certain psychological and social impairments remain. In some cases, therapy may be helpful in improving functioning: For example, Dialectical Behavior Therapy is one approach commonly used to treat borderline personality disorder.

What Shapes Personality?

As we learn about how much and in what ways personalities develop over time, questions still abound about what, exactly, gives a person a particular set of traits to begin with. As with other psychological characteristics, personality traits are influenced by one’s genes as well as other factors—and not necessarily the ones we think.

What leads to differences in personality?

Many theories have been offered over the centuries, and there are still differences of opinion. But contemporary scientific research indicates that some portion of personality differences are explained by people’s genes, a small proportion at most is linked to environmental influences shared within a family, like parenting, and much of the differences result from many other non-genetic developmental factors. Some theorists propose that social role changes influence personality in significant ways as a person grows up.

How much of personality differences are genetic?

Estimates suggest the amount of difference between people (or variance) in personality ratings that can be attributed to genes—the heritability of personality—is less than half. A 2015 analysis gave an overall estimate of 40 percent, though it varied depending on the type of study. These figures are based on studies of twins and other approaches for exploring the contribution of genetic and non-genetic factors. Genome-wide association studies (GWAS) are now used to explore the specific links between many small genetic differences and people’s traits.

Does birth order affect personality?

Despite popular ideas and psychological theorizing about the effects of being a firstborn sibling, the “baby” of the family, or a middle child, recent studies show no evidence that birth order plays a substantial role in shaping personality. Research on only children has also found little to no difference between their personalities and those of others.