Trait theory is among the oldest approaches to explaining personality. According to this approach, your personality is the result of some external force.
The advantage to trait theory is that discovering who you are is relatively simple. You take a test, read a book, check your horoscopes or hire someone to analyze your star charts. The assumption is that there is an answer to who you are, and that the answer is knowable. It might take effort but someone will tell you who you are.
The disadvantage to trait theory is that you are locked into whatever traits someone else says you have. If you are labeled an introvert, you can never change. Outgoing people can never be shy. Trustworthy people can never cheat. Cowards can never become a hero. Trait theory is a closed system. There is no way out.
Ancient Trait Theories
For the ancient Chinese, who you are is determined by the year in which you are born. If you are born in the year of the rat, your personality and fortune will be different from someone born in the year of the ox. About 3500 years ago, the Chinese developed a system of personality based on when you were born. This zodiac incorporated the planets (5 elements), the months (12 animals), and (later on) the tide: yin and yang. This 60-year cycle explained what you were like, who to marry, and what would happen in the future. Many ancients believed that your name determines your personality. The power of names was so great, parents carefully chose a name lest they temp the fates. Consequently, naming a baby “sloth” would be unacceptable, while naming a child “brave” or “mercy” would produce a person held that trait.
The ancient Greeks explained personality by four elements of life. About the time of Confucius, Hippocrates was explaining to the Greeks that personality types (humors) were based on four essential body fluids. A balance of the four fluids (yellow bile, phlegm, black bile and blood) kept one in “good humor.” A bit too much blood (sanguine) makes one confident and brave; too much makes someone arrogant, impulsive and unpredictable. A bit phlegmatic makes one easy going; too much makes on sluggish and lazy. A bit of yellow bile (choleric) gives one energy and passion; too much makes one aggressive and bad-tempered. Being a bit melancholic makes one sensitive and poetic; too much drowns you in depression. You might be born sanguine (happy) or melancholic (sad) but your temperament was predetermined by these elements.
Ancient approaches often emphasized temperament over character. Temperament was thought to be the built-in characteristics a person has. You might have a generally sad personality (melancholy) or happy (sanguine). This temperament doesn’t mean you can’t be honest (character) but describes your general bent. If you’re a morning person, it’s the result of temperament. If you go to an early morning class even though you are a late-night person, it’s a reflection of your character.
Modern Trait Theories
The first modern personality trait theorist was Gordon Allport. In the 1930’s, Allport and his students searched through dictionaries to find words that described personality. They started with 17,953 adjectives but settled on 4504 of them. Allport suggested that most of these traits were “common traits” (traits we all hold in common). Some might have a lot of a common trait but others might have only a smidge. But Allport also proposed that people can have individual traits unique to them. His morphogenic approach combined individual uniqueness (idiographic traits) and group comparison traits (nomothetic traits). You can compare yourself to others on “agreeable,” “friendly,” and “caring.” Plus, you can have your own special nobody-in-the-world-is-like-me traits. Allport bridged the “lots of traits” and the “only a few traits” debate by combining them.
Following Allport’s lead, Raymond Cattell reduced Allport’s list further. Cattell removed uncommon words and those he thought redundant. He whittled it down to 171 traits. Still following Allport’s lexical approach (personality can be described by dictionary words), Cattell added a statistical technique: factor analysis. He believed that a limited number of traits were underlying the thousands of words used to describe people. Cattell was among the first to use factor analysis to determine which words went together and which described a different trait. He ended up with 16 factors (traits). His personality test, the 16 PF (sixteen personality factors) is still in use today. Cattell’s factors included: affectia (outgoing vs. reserved), ego strength (emotional volatility), parmia (adventurousness), and surgency (a sort of happy-sad distinction).
Cattell wasn’t the only one using factor analysis. Hans Eysenck used the statistical technique to reduce personality to two dimensions: neuroticism and introversion-extroversion. For Eysenck, personality was more a matter of temperament than character. He revived the humors of Hipprocates but reformulated the four humors into two dimensions: extroversion and neuroticism. Extraversion is a reflection of your physiological make up. He believed that your shy personality is the result of your brain is easily startled. Specifically, Eysenck targeted the ascending reticular activating system (ARAS) and the reticular formation of the lower brain stem. Introverts, according to this view, don’t have the safety mechanism that extroverts do. When trouble comes, an extroverts brain becomes numb or zones out. This inhibition process protects the brain from trauma. In contrast, introverts feel all of the impact of the traumatic event and are overwhelmed by it.
Although nervous people aren’t always neurotic, Eysenck believed that they were more susceptible to problems, hence the tendency for people to have “nervous disorders,” “nervous breakdowns,” and “nervous ticks.” This nervousness is the result of temperament: built in physiologically. Since the sympatric nervous system causes arousal and emotional responsiveness, he hypothesized that people who scored high on his test of neuroticism had an underlying physiology that made them more likely to be excited by danger and stress. People who remain calm under stress have a sympathetic nervous system that is less responsive.
The tendency to believe personality is biologically based is not limited to the brain physiology. In the 1940’s, William Sheldon proposed that personality and body types were linked. He categorized people as being endomorphic (soft and round), mesomorphic (muscular and rectangular) and ectomorphic (fragile and tall). According to this approach, soft and round folk were friendly and cuddly. But muscular mesomorphs were assertive and energetic. Ectomorphs might be thin and shy but they were smart. Sheldon’s theory was more phrenology than psychology, but you’ll still encounter people following his line of reasoning.
Henry Murray added to trait theory by hypothesizing two influences on people: needs and presses. Needs can be both processes and internal states (achievement, power, intimacy). Your need for intimacy pushes you toward people. Your need for achievement determines how hard to try. Just as hunger is a physiological need that pushes you to get food, psychological needs are internal pressures that compel action. Your behavior is not solely the result of your needs. The environment also impacts you. These environmental presses pressure you from the outside. You can be pressured by a press of danger, or deprivation. Your environment might press you to be friendly or compliant. You can be impacted by a rejecting environment, or one of loss or duty. Both a loss in your life and the birth of a child are presses. In some sense, you are trapped between internal drives and external presses.
Murray’s other main contribution to personality theory was the creation of the Thematic Apperception Test (TAT). Although today it is widely used as a test of creativity, the TAT was designed to reveal latent needs (unexpressed needs). Composed of a series of magazine-sized cards, the test is a collection of abstract images on which a person can “project” their personality. You would be given a card and asked to describe what is going on now, what went on before, and what is going to happen in the future. Your stories would be written down verbatim, and later analyzed for themes. Murray, who was psychoanalyzed by Carl Jung, believed that these latent themes were the key to understanding how people really felt; the TAT was a key to understanding one’s personality.
The most recent trait theory is a multidimensional theory called the Big Five. This is a consensus theory, not the work of a single person. It is the culmination of work over three decades using factor analysis. The Big Five are summarized as OCEAN or CANOE: openness, conscientiousness, extroversion, agreeableness and neuroticism.
In the 19060’s, the Air Force routinely gave Cattell’s 16PF to its incoming officers. Two researchers (Tupes & Christal, 1962) analyzed these tests, looking for underlying factors. From their eight samples (they didn’t look at all of the scores), they concluded that the number of personality factors could be reduced substantially from Cattell’s sixteen. In six of the samples, they could reduce the number of factors to eight. In another sample, they found 5 factors. In the last sample, they identified 12 factors.
Using undergraduates instead of Air Force personnel, another researcher (Norman, 1963) found five factors. Norman had students rate their peers on 20 of the variables Tupes and Christal used (four from each of the five factors). Through factor analysis, he found five factors (which critics suggest is not surprising since he started with 4 examples of each of the five factors). In another study (Norman, 1967), 1431 words were rated on the original five dimensions, resulting in 75 semantic clusters. These clusters were later used with others words but again five factors were found (Goldberg, 1980); again not a surprise to the critics: start with clusters based on five dimensions and end with five dimensions.
Another research team (McCrae & Costa, 1976) began with a two-trait model (neuroticism and extraversion) but later added “openness to experience.” Still later, they added agreeableness and conscientiousness (Costa & McCrae, 1985). In their personality test (NEO, each of the five factors are composed of six subscales (facets). So extroversion is really a combination of gregariousness, activity, assertiveness, warmth, positive emotions, and seeking excitement. And agreeableness is subdivided into trust, modesty, compliance, altruism, tendermindedness and straightforwardness.