Jung's Theory of Psychological Types and the MBTI® Instrument
This excerpt is taken from Chapter 1 of the 1985 MBTI®
Manual: A Guide to the Development and Use of the Myers-Briggs Type
Indicator®. It was based on the first version
of the Manual by Isabel Myers and written by Mary H. McCaulley,
Ph.D. and founding President of CAPT. The Manual was published by
CPP, Inc. The 3rd Edition of the Manual was published by CPP, Inc.
"The purpose of the Myers-Briggs Type Indicator®
is to make the theory of psychological types described by C. G.
Jung (1921/1971) understandable and useful in people's lives.
The essence of the theory is that much seemingly random variation
in behavior is actually quite orderly and consistent, being due
to basic differences in the way individuals prefer to use their
perception and judgment."
Perception involves all the ways of becoming aware of things, people,
happenings, or ideas. Judgment involves all the ways of coming to
conclusions about what has been perceived. If people differ systematically
in what they perceive and in how they reach conclusions, then it
is only reasonable for them to differ correspondingly in their interests,
reactions, values, motivations, and skills.
The MBTI instrument is based on Jung's ideas about
perception and judgment, and the attitudes in which these are used
in different types of people. The aim of the MBTI
instrument is to identify, from self-report of easily recognized
reactions, the basic preferences of people in regard to perception
and judgment, so that the effects of each preference, singly and
in combination, can be established by research and put into practical
The MBTI instrument differs from many other personality
instruments in these ways:
- It is designed to implement a theory; therefore the theory
must be understood to understand the MBTI instrument.
- The theory postulates dichotomies; therefore some of the psychometric
properties are unusual.
- Based on the theory, there are specific dynamic relationships
between the scales, which lead to the descriptions and characteristics
of sixteen "types."
The MBTI instrument contains four separate indices.
Each index reflects one of four basic preferences which, under Jung's
theory, direct the use of perception and judgment. The preferences
affect not only what people attend to in any given situation, but
also how they draw conclusions about what they perceive.
The E–I index is designed
to reflect whether a person is an extravert or an introvert in the
sense intended by Jung. Jung regarded extraversion and introversion
as "mutually complementary" attitudes whose differences "generate
the tension that both the individual and society need for the maintenance
of life." Extraverts are oriented primarily toward the outer world;
thus they tend to focus their perception and judgment on people
and objects. Introverts are oriented primarily toward the inner
world; thus they tend to focus their perception and judgment upon
concepts and ideas.
The S–N index is designed to reflect
a person's preference between two opposite ways of perceiving; one
may rely primarily upon the process of sensing (S), which reports
observable facts or happenings through one or more of the five senses;
or one may rely upon the less obvious process of intuition (N),
which reports meanings, relationships and/or possibilities that
have been worked out beyond the reach of the conscious mind.
The T–F index is designed to reflect
a person's preference between two contrasting ways of judgment.
A person may rely primarily through thinking (T) to decide impersonally
on the basis of logical consequences, or a person may rely primarily
on feelings (F) to decide primarily on the basis of personal or
The J–P index is designed to describe
the process a person uses primarily in dealing with the outer world,
that is, with the extraverted part of life. A person who prefers
judgment (J) has reported a preference for using a judgment process
(either thinking or feeling) for dealing with the outer world. A
person who prefers perception (P) has reported a preference for
using a perceptive process (either S or N) for dealing with the
The Four Preferences of the MBTI instrument
E Extraversion or
Affects Choices as to
Whether to direct perception judgment mainly on the outer world (E) or mainly on the inner world of ideas.
S Sensing perception or
N Intuitive perception
Affects Choices as to
Which kind of perception is preferred when one needs or wishes to perceive
T Thinking judgment or
F Feeling judgment
Affects Choices as to
Which kind of judgment to trust when one needs or wishes to make a decision
J Judgment or
Affects Choices as to
Whether to deal with the outer world in judging (J) attitude (using
T or F) or in the perceptive (P) attitude (using S or N)
The Sixteen Types
According to theory, by definition, one pole of each of the four
preferences is preferred over the other pole for each of the sixteen
MBTI types. The preferences on each index
are independent of preferences for the other three indices, so that
the four indices yield sixteen possible combinations called "types,"
denoted by the four letters of the preferences (e.g., ESTJ, INFP).
The theory postulates specific dynamic relationships between the
preferences. For each type, one process is the leading or dominant
process and a second process serves as an auxiliary. Each
type has its own pattern of dominant and auxiliary processes and
the attitudes (E or I) in which these are habitually used. The characteristics
of each type follow from the dynamic interplay of these processes
Processes and attitudes
Attitudes refer to extraversion (E) or introversion (I).
Processes of perception are sensing (S) and intuition
Processes of judgment are thinking (T) and feeling (F).
The style of dealing with the outside world is shown by judgment
(J) or perception (P).
In terms of the theory, people may reasonably be expected to develop
greater skill with the processes they prefer to use and with the
attitudes in which they prefer to use these processes. For example,
if they prefer the extraverted attitude (E), they are likely to
be more mature and effective in dealing with the world around them
than with the inner world of concepts and ideas. If they prefer
the perceptive process of sensing (S), they are likely to be more
effective in perceiving facts and realities than theories and possibilities,
which are in the sphere of intuition. If they prefer the judgment
process of thinking (T), they are likely to have better developed
thinking judgments than feeling judgments. And if they prefer to
use judgment (J) rather than perception (P) in their attitude to
the world around them, they are likely to be better organizing the
events of their lives than they are to experiencing and adapting
to them. On the other hand, if a person prefers introversion, intuition,
feeling, and the perceptive attitude (INFP), then the converse of
the description above is likely to be true.
Identifying the MBTI Preferences
The main objective of the MBTI instrument is to
identify four basic preferences. The indices E–I, S–N, T–F, and J–P
are designed to point in one direction or the other. They are not
designed as scales for measurement of traits or behaviors. The intent
is to reflect a habitual choice between rival alternatives, analogous
to right handedness or left-handedness. One expects to use both
the right and left hands, even though one reaches first with the
hand one prefers. Similarly, every person is assumed to use both
poles of each of the four preferences, but to respond first or most
often with the preferred functions or attitudes.
The 16 Types
As located on the Type Table