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The set of psychological traits and
mechanisms within the individual that are
organized and relatively enduring and that
influence his or her interactions with, and
adaptations to, the intrapsychic, physical, and
social environments.
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Characteristics that describe ways in which
people are different from each other.
Traits also define ways in which people are
similar to each other.
Finally, they describe the average tendencies
of a person.
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How many traits are there?
How are the traits organized?
What are the origins of traits?
What are the correlations and consequences
of traits?
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They help describe people.
They help explain behavior.
They help predict future behavior.
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They are organized and not simply a random
collection of elements. Traits are linked to each
other systematically.
They’re relatively enduring over time and are
somewhat consistent across situations.
The idea of consistency across situations has a
long history of debate, but most personality
psychologists now believe people are relatively
consistent.
Difference between states and traits—for
instance, anger is a state but hot-tempered is a
trait.
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Perceptions—how we interpret an
environment
Selection—how we choose our friends,
careers, hobbies, etc. (How we use our free
time is especially a reflection of our
personalities.)
Evocations—reactions we produce in others,
often unintentionally
Manipulations—the ways in which we
intentionally try to influence others
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Our personalities help us adapt to the
environment—accomplish goals, cope, and
deal with the problems we face.
Psychologists’ knowledge of the adaptive
function of personality is currently limited.
Adaption to the environment includes both
physical and social environment.
Social environment includes things such as
our need for belongingness, love, and
esteem.
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Human nature
◦ Need to belong
◦ Capacity for love
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Individual and Group Differences
◦ Variation in need to belong (individual difference)
◦ Men more physically aggressive than women (group
difference)
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Individual Uniqueness
◦ Person X’s unique way of expressing love
◦ Person Y’s unique way of expressing aggression
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A debate in the field: Should individuals be
studied nomethetically or idiographically?
Nomothetic research involves groups of people—
requires samples of subjects
◦ Usually applied to individual and group difference
research
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Idiographic research involves single subjects to
try to observe general principles that are
manifest over a single life over time.
◦ The term “idiographic” literally means “the description of
one.”
◦ Case studies/psychological biographies of one person
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Grand theories vs. contemporary research
Stated another way, the gap between human
nature level of analysis (“grand theories”) vs.
group and individual differences
(“contemporary research”)
Most textbooks in Personality focus on grand
theories.
This gap has not yet been successfully
bridged.
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Dispositional
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Biological
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Intrapsychic
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Cognitive-experiential
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Social and Cultural
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Adjustment
◦ How people differ from each other (traits)
◦ Genetics, psychophysiology, and evolution
◦ The role of the unconscious; research on motives (many of which
are unconscious)
◦ Conscious thoughts, beliefs, feelings, and desires; past vs. future
selves, self-esteem
◦ How different cultures display different personalities; how our
personalities affect our social lives
◦ How personality helps us cope and adapt to our lives; how
personality is related to health
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A good theory fulfills three purposes:
◦ Serves as a guide for researchers
◦ Organizes known findings
◦ Predicts behavior and psychological phenomena
that have not yet been studied.
Theories differ from beliefs, such as astrology,
because they can be tested by systematic
observations that can be repeated by others and
yield similar conclusions.