The trait theory of personality suggests that people have certain basic traits or dispositions, and it is the strength and intensity of those traits that account for personality differences. The trait approach to personality is one of the major theoretical areas in the study of personality.

A trait is a consistent, stable characteristic that causes individuals to behave in certain ways, it varies from person to person.

The outlook towards personality, and how traits are defined, has evolved over time. Unlike many other theories of personality, such as psychoanalytic or humanistic theories, the trait approach to personality is focused on differences between individuals/

The combination and interaction of various traits is unique to each person. Trait theory is focused on identifying and measuring these individual personality characteristics.

If someone asked you to describe a close friend's personality, what kind of things would you say? A few things that might come to mind are descriptive terms such as "outgoing," "kind" and "even-tempered." All of these represent personality traits.

Allport’s Trait Theory
The first trait theory was proposed by psychologist Gordon Allport in 1936. Allport found that one English-language dictionary contained more than 4,000 words describing different personality traits. He categorized these traits into three levels: cardinal, central, and secondary.

Cardinal Traits
Allport suggested that cardinal traits are rare and dominating, usually developing later in life. They tend to define a person to such an extent that their names become synonymous with their personality. Examples include descriptive terms such as Machiavellian, narcissistic, and Christ-like.

Central Traits
These general characteristics form basic personality foundations. While central traits are not as dominating as cardinal traits, they describe the major characteristics you might use to describe another person. Descriptions such as "intelligent," "honest," "shy," and "anxious" refer to central traits.

Secondary Traits
Secondary traits are sometimes related to attitudes or preferences. They often appear only in certain situations or under specific circumstances. Some examples include public speaking anxiety or impatience while waiting in line.

Cattell’s 16-Factor Personality Model
Trait theorist Raymond Cattell reduced the number of main personality traits from Allport’s initial list of over 4,000 down to 171. He did so primarily by eliminating uncommon traits and combining common characteristics.

Next, Cattell rated a large sample of individuals for these 171 different traits. Using a statistical technique known as factor analysis, he identified closely related terms and eventually reduced his list to 16 key personality traits. Among them are dominance, perfectionism, reasoning, and self-reliance.

According to Cattell, these 16 traits are the source of all human personalities. He also developed one of the most widely used personality assessments, the 16 Personality Factor Questionnaire.

Eysenck’s 3 Dimensions of Personality
British psychologist Hans Eysenck believed that personality has a biological basis, developing a model of personality based on just three universal traits.

Introversion/Extraversion
Introversion involves directing attention to inner experiences, while extraversion relates to focusing attention outward, onto other people and the environment. A person high in introversion might be quiet and reserved, while an individual high in extraversion (often spelled "extroversion") might be sociable and outgoing.

Neuroticism/Emotional Stability
This dimension of Eysenck’s trait theory is related to moodiness versus being even-tempered. The trait of neuroticism refers to an individual’s tendency to become upset or emotional, while stability refers to the tendency to remain emotionally constant.

Psychoticism
Later, after studying individuals with mental illness, Eysenck added a personality dimension he called psychoticism to his trait theory. Individuals who are high in this trait tend to have difficulty dealing with reality and may be antisocial, hostile,

Big-Five Model of Personality
personality represents five core traits that interact to form human personality. While researchers often disagree about the exact labels for each dimension, they are commonly described as:

Agreeableness: level of cooperation and caring for others
Conscientiousness: level of thoughtfulness and structure
Extraversion: level of socialness and emotional expressiveness
Neuroticism: level of mood stability and emotional resilience
Openness: level of adventure and creativity

Criticisms of Trait Theory
Most theorists and psychologists agree that people can be described based on their personality traits.

Some of the most common criticisms of trait theory center on the fact that traits are often poor predictors of behavior.

Girish Kishnani
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