An age-old question which most people have pondered at some point
in their lives is "why are we the way we are"? Unfortunately, I can't clue
you in on the answer to that question in a really authoritative way, but
I can tell you about work that has been done to determine how people's
Personality Types are developed.
The more recent studies done around Temperament suggest that we are
each born with our temperaments intact. Efforts are being made to
prove this. For more information about temperaments, click
here.
W. Harold Grant did a lot of work with Jung's theories, and concluded that Jung
believed that Personality Type has a developmental process which can be
observed through an individual's life. The early phases of our lives help
determine the dominance ordering of the four functions (Sensing, Intuition,
Thinking and Feeling), and the development of our dominant and auxiliary functions.
The later phases help us develop our tertiary and inferior functions.
Let's take a look at Grant's phases of development, using the INFJ
Personality Type as an example:
From age 0 - 6 years
At this early age, we use all four of the functions in an indiscriminate
fashion. We "try on" the different functions for size, determining which
ones work best for us. The little INFJ has not yet emerged as any
particular personality type, although his parents may notice trends in
behavior which appear to have the characteristics of one or more types.
From 6 - 12 years
During this phase, our dominant function begins to develop and assert itself.
Our young INFJ begins to appear dreamy and introspective - he begins
to prefer to use his iNtuition to take in information, and he
chooses to do this alone (Introverted). The dominant function of
"Introverted iNtuition" begins to show itself as the prevailing aspect
of his personality.
From 12 - 20 years
The auxiliary function asserts itself as a powerful support to the
dominant function. Since all recent studies point towards the importance
of a well-developed team of dominant AND auxiliary functions, this is an
important time of "self-identification". Research suggests that people
without a strong auxiliary function to complement their dominant function
have real problems.
In our INFJ example, we see the auxiliary Feeling function come to the front
during this phase
as a support to the dominant iNtuitive function. Since the INFJ's dominant
function is an Information Gathering function, the auxilary function must be
a Decision Making one. Without a Decision Making process, we would
flounder about and never get anything done! As the auxilary Feeling process
comes forth, the INFJ begins to develop the ability to make decisions based
on his personal value system. This auxiliary decision making process will be
Extraverted, since the dominant function is Introverted.
Since the decision making function is Extraverted, our subject now emerges
as a "Judger", rather than a "Perceiver". Our INFJ Personality Type is
now pretty firmly set in place, and we know the dominance ordering
of the four functions.
From 20 - 35 years
We begin to use our tertiary function more frequently and with better success.
Our INFJ begins to use his Introverted Thinking function. He continues
to make judgments with his Extreverted Feeling auxiliary function, but he
also begins to make judgments based on logic and reason, which he works
through in his own mind, rather than discussing it with others.
From 35 - 50 years
We pay attention to our fourth, inferior function. We feel a need to
develop it and use it more effectively. Our INFJ begins to use his
Extraverted Sensing function. He becomes more aware of his surroundings
and begins to take in information from others in a more literal, practical
sense. He continues to rely on his dominant Introverted iNtuitive function
to take in information, but he is more able to use his Extraverted Sensing
function than he has been before in his life.
Some researchers have attested that the appearance of our inferior
functions at this phase of life may be responsible for what we commonly
call the "mid-life crisis".
From 50 onwards
From this age until our deaths, we have accessibility to all four functions.
However, we use them in a more disciplined, differentiated manner than
when we were very young. Our basic Personality Type continues to assert itself,
but we are able to call upon all four functions when needed.
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