Psychologist seek simple, but powerful ways to categorize people to allow for predictions
Understanding Human Personality
Central- what make us different from others
o Scientific study of individual differences.
o Consistency versus individuality; enduring and unique characteristics and traits that
are persistent over time and space.
o Intrapersonal processes
A look at the self, the subjective, private part of us that lend coherence and
order to our behaviour.
o For the average person, personality is often in terms of attractiveness (ex. She has a
Theories of Personality
What are the sources of consistent behaviour patterns and intrapersonal processes?
Type and Trait Perspectives
Type theories classify people according to one or another distinct personality types
o Non-overlapping categories
Hippocrates, 5th Century B.C.
Fluid types; personality based on dominant type present.
o Modern barber shop pole representative of "blood letting"
William Sheldon, 1942
Endomorph, Mesomorph, and Ectomorph
Frank Sulloway, 1996
o Born to rebel- birth order
o Darwin- organisms diversify to find niches in which they'll survive. First borns have a
ready-made niche while later borns have to carve out new ones. However, there is
mixed data on this topic as there are a variety of factors.
Myers-Briggs & The P.T. Barnum Effect
o Used by employers yet it’s supported by weak data
o The Forer/Barnum Effect
Took personality test, but everyone received the same result that was based
on a horoscope found in the paper that day. The average rating they gave the
accuracy was 4.2/5.
Pseudoscience and Personality
Subjective/personal validation effect
Tendency to accept vague and general personality descriptions as uniquely
Problems with Types
Strict type approach makes several assumptions not easily justified
o Even seen with Type A and Type B personalities
Trait Approach (Gordon Allport, 1937)
o Traits are dispositional to behaviour o Personality traits are relatively stable over time
o Personality trait are consistent over situations
o Situations are "functionally equivalent"
Situational versus personality
o Individual differences result from differences in the strength and combination of
Gordon believed that the words we used to describe ourselves/others provides a window
on the human personality. Words can be separated into 3 types:
1. Generalized dispositions called cardinal traits (one word descriptions; ex. Honest
2. Central Traits are less pervasive but still generalized dispositions.
3. Secondary Traits; more specific, narrow traits such as anxiety before a test or
Sam Gosling (2002)
o Does your room give away your personality?
Neat people more likely to be introverts and extraverts are more messy
Behavioural residue (like secondary traits) show changeable aspects of
personality, but still offer clues about a person at a specific time in their life.
Common Versus Unique Traits
Cattell agreed with Allport
Problem was to identify the few basic traits (source)
He used factor analysis to analyze the correlations among a large number of variable, in
this case trait words. The goal was simplification.
Trait co-variation s define high order factors (ex. Humorous, amusing, and popular have
high correlations and potentially one source; therefore one word could be used).
Cattell's 16 Personality Factors
The Big Five (The OCEAN of Personality)
Emerged from ratings using English language trait adjectives
Based on degrees/scales you fall on for individual differences
Supported by cross cultural analysis and heritable analysis.
Big 5 +/- 3 or More
Melancholic, choleric, Phlegmatic, and Sanguine. Based on stability and extroversion
Criticisms of Trait Approach
Circular reasoning (does the trait of behaviour come first).
Largely descriptive, but lacks explanation
Static, doesn't address personality growth
Statistics appear more objective/impressive than they really are.
However, trait approaches that link to biological/genetic factors are more powerful then
Trait approach assumes consistency
The person-situation controversy
o Walter Mischel
Specific behaviours from one situation to the next are not always consistent in
the same person
Although people's traits persist over time, human behaviour varies widely from
situation to situation with a cross-situational consistency of <0.30.
o Cheating and Stealing Study
Both of these behaviours are dishonest, but there was no correlation found
between the two behaviours.
o Situationists versus Dispositionists
Person by situation interactions (ex. An otherwise stable individual may
become neurotic over a bad grade).
Personality lies in if-then patterns
Consistency most likely to emerge in similar situations
Taken to its extreme, views traits as mere illusions
See people in the same situation time and time again so we tend to associate the
behaviours with their personalities based on this.
Has been met with strong criticism
Over long periods of time and over many situations consistency is evident.
Synthesis of traditional trait view and situationism- person x situation interaction
Bandura called this Reciprocal Determinism
o Personal/cognitive factors interact with the environment to influence people's
o "I won't do well in this class, so I will socialize instead and fail".
Nature and Nurture of Personality
To what extend are your parents responsible for who you are?
Tendency t blame/credit parents Parents do have n important influence on personality
o Our first real close relationship with others
Affect our expectations with relationships
Temperaments are different at birth
Heritability of Big 5=0.5
Personality of adopted children are not at all related to the personality of their adoptive
o Many formative life experiences occur without the presence of parents
Forming relationships with peer is more important than doing so with parents
Judith Harris, 1998