<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Archiving and Interchange DTD v1.0 20120330//EN" "JATS-archivearticle1.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>September</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>A Jungian based framework for Artificial Personality Synthesis</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>David Mascarenas</string-name>
          <email>dmascarenas@lanl.gov</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Los Alamos National Laboratory - Engineering Institute PO</institution>
          <addr-line>Box 1663 MS T001 Los Alamos, NM, 87544 1-505-665-0881</addr-line>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2016</year>
      </pub-date>
      <volume>16</volume>
      <issue>2016</issue>
      <abstract>
        <p>The field of computational intelligence has enjoyed much success in developing a variety of algorithms that emulate human cognition. However, a framework to tie these algorithms together in a coherent manner to create a machines that possess the full spectrum of human-like personalities is still needed. To date, research on artificial personality synthesis has focused on using the Big Five model from the field of personality psychology. The overlooked Achilles heel of Big Five (BF) is that it is purely datadriven model, and thus offers only marginal guidance on how a machine with a personality might actually be created. In this work an alternative computational personality framework is presented based on the work of Carl Jung. There are two key insights that suggest a Jungian type-based framework is suitable for synthesizing an artificial personality. First, the cognitive functions which form the building blocks of the Jungian personality model can be mapped to classes of algorithms used to emulate cognition. Second, the Jungian framework suggests that at any given time humans are only using one of the cognitive functions. This suggests that a human personality could be emulated using a state machine with each state implemented using the appropriate class of algorithms.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;artificial personality synthesis</kwd>
        <kwd>Carl Jung</kwd>
        <kwd>affective computing</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>CCS Concepts</title>
      <p>• Human-centered computing➝Interaction
concepts and paradigms
design theory,</p>
    </sec>
    <sec id="sec-2">
      <title>1. INTRODUCTION</title>
      <p>The advent of ubiquitous computing has increased interest in
techniques for endowing a machine with a human-like
personality. Vinciarelli [1] provides an overview of personality
computing research which shows that since 2006 a marked
increase in research papers with the word “personality,” included
in the title. Vinciarelli makes one particularly interesting
statement with regards to the nature of the work that has been
undertaken thus far, “Trait based models are widely accepted in
the computing community as well. All of the works surveyed in
this article adopt personality traits (the BF in 76 cases out of 81)
and, to the best of our knowledge, no other theories were ever
adopted in computing oriented research. On one hand, this barely
reflects the dominant position of trait based models in personality
psychology. On the other hand, trait-based models represent
personality in terms of numerical values, a form particularly
suitable for computer processing. [1].” This statement raises an
interesting question. Why has computational personality research
thus far restricted itself to exploring trait-based models of
personality? Vinciarelli points out a number of competing
personality models including: psychoanalytic, cognitive, and
behaviorist and biological. Arguably, personality models such as
the biological model may currently not be adequately understood
to be implemented on a computer, and as Vinciarelli points out,
the numerical nature of trait-based models may be amenable to
computer implementation to a degree. However, the nature of the
Jungian type-based model also lends itself to implementation on a
computer, but to the best knowledge of the author has not been
explored to date. This work will outline how Jungian
psychological type theory can be used as guidance to synthesize
an artificial personality.</p>
      <p>This Jungian type-based framework possesses a number of
attractive properties. First, a very large fraction of algorithms
emulating cognitive processes can be utilized by the framework in
a coherent manner. Second, the framework can arguably
synthesize the full spectrum of human personalities. Third,
Jungian-based personality theory is very popular among
laypeople. Modern personality psychologists might argue that this
is due to the cognitive bias known as the Barnum effect. From a
Turing test perspective however this is irrelevant, and perhaps
even an advantage because it would facilitate the illusion of a
machine having a human-like personality For practical
applications all that really matters is that the machine can
convince a human that it has a personality.</p>
    </sec>
    <sec id="sec-3">
      <title>2. THE JUNGIAN PERSONALITY TYPE</title>
    </sec>
    <sec id="sec-4">
      <title>MODEL</title>
      <p>Carl Jung is probably most popularly known for introducing
the concept of the “introvert,” and “extrovert.” Jung detailed
his theory of psychological types in 1921 [2], [3]. Jung’s
model for personality is based on the idea of “cognitive
functions.” Jung identified two fundamentally different kinds
of cognitive functions known as “perception,” and
“judgement. [4]” Perception describes how a person takes in
information, and judgment pertains to decision-making. Jung
then broke these classes down further. Jung asserted that
perception came in two main forms: “sensation” and
“intuition.” Sensation is focused on physical reality:. It tends
to focus on the present and past. Intuition is primarily focused
on finding meaning, patterns, or possibilities in information.
The tendency is to focus more on the future [5]. Likewise,
Jung identified two forms of judgement which he referred to
as “thinking,” and “feeling.” Thinking refers to
decisionmaking processes that focus more on the application of basic
truths/principles. It tends to impersonal in the sense that it
resists allowing personal value judgements, or the value
judgements of others influence decision making. Conversely,
“Feeling,” puts significant weight on values. These values can
be either personal or shared by a community. It tends to prefer
decisions that will result in harmony [6]. Jung then further
refined his cognitive functions by asserting that each of the
four functions has an introverted and extroverted orientation.
An introverted orientation implies a tendency towards a
person’s interior world of thoughts, ideas, feelings and
memories. An extroverted orientation focuses on people or
experiences external to the self [4]. Jung’s clinical
observations and reflection ultimately resulted in a total of 8
cognitive functions. For completeness the eight cognitive
functions are:</p>
      <p>Extroverted Thinking
Introverted Thinking
Extroverted Feeling
Introverted Feeling
Extroverted Sensing
Introverted Sensing
Extroverted Intuition
Introverted Intuition
(Te)
(Ti)
(Fe)
(Fi)
(Se)
(Si)
(Ne)
(Ni)
For the sake of brevity, a full description of Carl Jung’s 8
cognitive functions will not be provided in this document.
Since Jung initially introduced the concept of cognitive
functions, the language used to describe them has evolved as
has an understanding of their nature. For the purpose of this
work, the cognitive function descriptions provided in [4] will
be used throughout this work.</p>
      <p>In 1923, Katherine Briggs and her daughter Isabel Briggs
Meyers were exposed to the newly available English
translation of “Psychological Types” [7], [8] At the time
Katherine was in the process of developing her own
personality theory motivated partially by a desire to
understand the personality of her son-in-law. Upon reading
Jung’s work they came to the conclusion that Jung’s theory
was superior to their own and so decided to adopt and refine
the Jungian model. Over the next 20 years the
motherdaughter team obsessively observed and documented human
nature with regards to type. They eventually created a
variation on Jung’s system with an associated sorting
instrument known as the Myers-Briggs Type Indicator
(MBTI).</p>
      <p>The evolution of Jung’s psychological type proposed by
Myers and Briggs had a few important characteristics that are
worth mentioning. First, Myers and Briggs observed that all
people used all of the cognitive functions. The dissimilarity
between different types of people was the preference with
which they used the cognitive functions. In this model each
person uses the cognitive functions in a hierarchical manner
with a dominant cognitive function, followed by an auxiliary,
tertiary and inferior cognitive functions. Classically, Meyer &amp;
Briggs focused on the first four cognitive functions.
Furthermore, Myers &amp; Briggs introduced very specific
constraints on the hierarchical order the cognitive functions
were allowed to assume. One of the constraints Meyers &amp;
Briggs introduced was that the hierarchy of cognitive
functions had to alternate between introverted and extroverted
orientations. It is worth noting that the writing of Carl Jung
can be interpreted to indicate a different scheme for ordering
the cognitive functions, and competing ordering systems are
in existence. For the sake of clarity, the author tends to prefer
the ordering system outlined in [4]. However, with regards to
artificial personality synthesis, the framework outlined in this
work is flexible enough to be adapted to any desired cognitive
function ordering scheme.</p>
      <p>Ultimately, based on their imposed constraints on cognitive
function order, Meyers &amp; Briggs identified 16 unique
personality types. These personality types were given
fourletter labels. The first letter is either E or I to indicate an
introverted or extraverted orientation of the dominant
cognitive function. The second letter is either S or N to
indicate the dominant perception preference of sensation or
intuition respectively, the third label is T or F to indicate the
preferred judging cognitive function of either thinking or
feeling, and the last letter is either J or P to indicate whether
or not the preferred perception function has an introverted
orientation (J) or an extroverted orientation (P). An example
of a personality label from the use of this model would be
ENTJ. This would indicate a personality who’s dominant
function is extroverted thinking with introverted intuition as
the auxiliary perceiving function. The constraints imposed by
Meyers &amp; Briggs on the cognitive function order would then
further specify that the tertiary function is extroverted sensing
and the inferior function is introverted feeling.</p>
      <p>There is a very widely held misconception that each of the
four letters indicates a dimension of personality, like that
found in the Big-5 model. It cannot be stressed enough that
the four letters used to provide a personality label are in no
way representative of dimensions. It is more appropriate the
think of each grouping of four letters as a label. The Jungian
model is not based on the concept of dimensions in any way.
It is based on the concept of cognitive functions and the
hierarchical preference with which people with different types
of personality use them. Another common misconception is
that the Jungian/Meyers &amp; Briggs model implies a binary
distinction between -for instance- thinkers and feelers, or
judgers and perceivers. The common criticism is that the
model implies that a person solely uses only one class of
cognitive function or the other. For example, that a person is
either a thinker or a feeler. Once again this is not how the
theory works. The theory indicates that all people have access
to use all the cognitive functions. It is just that people have
different orders of preference for different functions.
Alternatively, Berens and Nardi [4] explain the preference in
terms of energy expenditure. They describe the use of a given
cognitive function as requiring the expenditure of more or
less energy depending on a person’s personality type.
Thinking of cognitive function use in terms of energy usage is
a very convenient way to guide the selection of cognitive
function to use in a given situation because it interfaces well
with computational thinking on cost functions in optimization
as well as with results in psychology that suggest that
selfregulation relies on glucose/energy levels [9].</p>
    </sec>
    <sec id="sec-5">
      <title>3. A FRAMEWORK FOR MAPPING</title>
    </sec>
    <sec id="sec-6">
      <title>JUNGIAN COGNITIVE FUNCTIONS TO</title>
    </sec>
    <sec id="sec-7">
      <title>ALGORITHMS FOR EMULATING</title>
    </sec>
    <sec id="sec-8">
      <title>PERSONALITY</title>
      <p>The proposed Jungian type-based framework for artificial
personality synthesis is based on three key principles.
1. Algorithms that have been developed to emulate
cognition (e.g. Principle Components Analysis [10],
Artificial Neural Networks, Linear Classifiers, etc.)
can be mapped to the cognitive functions that make
up the building blocks of the Jungian personality
model. These algorithms can be used to implement
the cognitive functions.
2. Human personality is inherently serial in nature.</p>
      <p>Human personality arises from the limitation that
humans can only use one cognitive function at any
given time. Or at least the human ability to use more
than one function at a time appears to be severely
limited.
3. The Jungian type-based personality framework
allows for the possibility of an individual agent to
use any of the 8 cognitive functions at any given
time, however, personality emerges from a
hierarchical preference for certain cognitive
functions over others. The order and magnitude of
preference can be selected based on models such as
the Myer &amp; Briggs cognitive function orders [4].</p>
      <p>They could also possibly be learned from data, or
could even be chosen arbitrarily. Initially the authors
suggest using the Myers &amp; Briggs cognitive function
orders as guidance.
is less common for the ENTJ machine to use extraverted
sensing (Se) and it rarely if ever transitions to the introverted
feeling (Fi) state. Personality is emulated by executing the
algorithms that correspond to the current cognitive function.
It is worth noting that alternatives to the Markov chain
representation could be envisioned. For instance, instead of
probabilities, the proclivity to transition to another cognitive
function could be couched in terms of energy costs associated
with the use of a cognitive function for a given personality
type as discussed in [4]. Also, please note that only 4
cognitive functions are shown in Figure 1. For completeness
all 8 cognitive functions could be included. Only the first 4
functions were used as is specified by the classic Myers and
Briggs framework for the sake of clarity. Lower order
functions were not included. In initial implementations of this
framework it might be preferable to only use the first 2
highest preference cognitive functions for the sake of
simplicity. The reason being that the first two cognitive
functions are all that is needed to distinguish one personality
type from the other 16. Furthermore Jungians tend to believe
the first two are the most important.</p>
      <p>In order to implement the Jungian type-based personality
framework, it is necessary to map algorithms that emulate
cognitive processes to the cognitive functions. Table 1.
provides a listing of the 8 cognitive functions, a short
description of each of the cognitive functions, and a list of
possible algorithms that could be used to emulate the
cognitive function. This list is by no means exhaustive, and
revisions are expected as artificial personality research
progresses. The descriptions provided in Table 1. borrow
heavily from [4] in order to maintain some uniformity in
descriptions.
The introverted and extroverted feeling judging functions
merit additional discussion. The feeling judging functions are
often associated with emotional response. The author
currently likes to think of emotional decision-making in
general to be similar to an artificial neural network in the
sense that an artificial neural network can often take many
complicated inputs and learn relationships between the inputs
that can be used to quickly make decisions, however it is not
always clear how exactly those decisions are made. The
author also prefers to think of the emotional cognitive
functions as being partially the results of an embodied
intelligence. Feeling judgements can be thought of as using
the body as an analog computer to perform simulations and
make decisions. Work by Nummenmaa [10] on mapping the
sensation of emotions felt in the human body lends some
support for this perspective.</p>
      <p>As an example of the application of the framework, a machine
endowed with an ENTJ personality using the Markov chain in
Figure 1, we might employ the A* algorithm to perform the
dominant extroverted thinking (Te) cognitive function to form
a plan to move through an environment. After the plans are
generated they might be analyzed in the introverted intuition
(Ni) state using an appropriate simulation that corresponds to
the environment and task of interest. If the simulation
verifies that the plan is acceptable the plan may be executed
by the extroverted Sensing function. In many cases the
machine may totally ignore the introverted feeling state and
proceed directly to execution, but when it does go into the
introverted feeling state it may use a neural network trained to
look out for the machine’s own well-being to decide whether
or not to actually execute the task based on whether or not the
machine “feels,” it will advance the machine’s self-interests.
It is also worth noting that creating the ability to endow
robots with personalities may also have application in human
machine teaming applications. Much as diversity in teams of
humans tends to lead to better results [4], endowing teams of
robots with different personalities may also lead to more
robust robotic teaming. For example, a team consisting of
humans could be augmented with machines endowed with
personalities different from the existing team members in
order to enhance the overall team diversity. Teams consisting
only of robots could be designed in such a way that individual
team members are endowed with complimentary
personalities, thus enhancing the overall robustness and
performance of the machine team.</p>
    </sec>
    <sec id="sec-9">
      <title>4. ADDRESSING SOME CONCERNS</title>
    </sec>
    <sec id="sec-10">
      <title>WITH THE JUNGIAN MODEL</title>
      <p>
        Since the MBTI was developed more than 10,000 companies,
2500 colleges/universities and 200 U.S. government agencies
have used the test [11]. It is estimated that more the 50
million people have used the instrument since 1962. Jungian
personality theory has had a great influence on corporate
America as well as popular culture. For instance, Carl Jung
popularized the terms introvert and extrovert. Despite the
popularity of Jungian personality theory in industry and
among laypeople, academia tends to discount it. One common
criticism against the MBTI is that it lacks test-retest
reliability [12]. The current perspective of the author is that
this criticism is probably valid. At this time the instrument
itself appears to have problems. The reason for the lack of
reliability with the current instruments may be that the
instrument is based on the analysis of a self-report inventory.
This type of instrument may be suitable if a Cartesian model
of personality is used, but the Jungian model is better
described as a dynamic system. Ultimately enhanced versions
of projective tests such as those suggested by Ottley [
        <xref ref-type="bibr" rid="ref1">13</xref>
        ], and
Brown’s [
        <xref ref-type="bibr" rid="ref2">14</xref>
        ] work may be better able to characterize human
personality. Another common criticism is that some Jungian
advocates made the claim that MBTI score distributions
assumed bimodal distributions, thus lending support to the
misunderstanding of Jungian theory that people fell into one
of two groups with respect to each letter in the Meyers-Briggs
labels. Some research suggests this bimodal distribution was
an artifact of the analysis techniques used [
        <xref ref-type="bibr" rid="ref3">15</xref>
        ]. The problem
with the original argument was that it was not necessarily
respecting the Jungian model as a dynamic system and was
making the assumption that the Jungian model could be
represented with a four dimensional Cartesian coordinate
system. It is not clear what type of distribution a personality
consisting of cognitive functions as building blocks should
generate when evaluated using a self-report inventory. A
central limit theorem argument could be made to suggest it
come out as a Gaussian, but to really make a definitive
statement a more rigorous analysis should be undertaken.
Ultimately when synthesizing an artificial personality, the
most important criteria for most applications is that the
personality be convincing to humans. As long as the machine
can pass a Turing-like test it is probably an acceptable
solution. The fact that the Jungian model is so widely popular
suggests that it may have a low barrier to acceptance among
the majority of the population.
      </p>
    </sec>
    <sec id="sec-11">
      <title>5. JUSTIFICATION FROM A</title>
    </sec>
    <sec id="sec-12">
      <title>NEUROSCIENCE PERSPECTIVE</title>
      <p>
        A number of interesting results have come out of the
psychology and neuroscience communities that lends some
support for the idea of using the Jungian type model as
outlined in this work. The idea that humans can effectively
only use one cognitive function at a time gains support from
the results of Watson [
        <xref ref-type="bibr" rid="ref4">16</xref>
        ] that suggest 98% of humans are
incapable of multitasking. Jack’s analysis of fMRI
measurements of the human brain suggested that there are
physiological constraints on our ability to simultaneously
engage two distinct cognitive modes. In this case they found
humans could not attend to tasks that require social cognition
and physical reasoning simultaneously [
        <xref ref-type="bibr" rid="ref5">17</xref>
        ]. Grondin (2015)
[
        <xref ref-type="bibr" rid="ref6">18</xref>
        ] found neuroanatomical differences between Agentic
(achievement-oriented) and Affiliative (sociable) extroverts.
From a Jungian perspective the concept of an agentic
extroverts corresponds very well with personality types with a
dominant extroverted thinking preference (ENTJ, ESTJ) and
affiliative extroverts correspond strongly with personality
types with a dominant extroverted feeling preference (ENFJ,
ESFJ).
      </p>
    </sec>
    <sec id="sec-13">
      <title>6. CONCLUSIONS</title>
      <p>Personality from a Jungian perspective can be thought of as a
zero sum game. Humans only have limited cognitive
resources, and our personality is based on how we tend to
choose to use those resources. This proposed framework is
particularly attractive because it uses established algorithms
as building blocks for personality. Because the building
blocks are algorithms, and in some cases learning algorithms,
the machine is ultimately able to learn and adapt to
experiences. The personality framework provides a genotype
so to speak but the ultimate phenotype of the machine
depends on the experiences it encounters throughout its span
of existence. This framework allows for great diversity in
resulting perceived personality phenotype.</p>
      <p>
        An interesting implication of the Jungian type-based
personality framework is that it might help in the
development of robust, high-performance human-machine
teams consisting of members with diverse personalities.
Observations on the personality diversity of teams and their
performance suggest that teams consisting of members with
diverse personalities tend to perform better [
        <xref ref-type="bibr" rid="ref7">19</xref>
        ]. A team
consisting of humans could be augmented by machines
endowed with personalities that enhance the team’s overall
personality diversity. Alternatively, teams consisting solely of
machines could consist of members who provide each other
with different perspectives of the world they are interacting
with.
      </p>
      <p>
        Experience has shown that data science problems often benefit
from the use of a combination of many heterogeneous models.
The Netflix prize provides a good example of showing the
advantages associated with simply combining different
approaches [
        <xref ref-type="bibr" rid="ref8">20</xref>
        ]. However contemporary computational
personality research is dangerously homogeneous in the sense that
all computational personality research is currently using a
traitbased paradigm [1]. The field would benefit from competing
models and approaches. Furthermore, from an engineering/Turing
test perspective it really does not matter whether or not the
approach used to generate an artificial personality accurately
models what is occurring in the human mind. It is only necessary
to convince the person interacting with it that it is a human-like
personality. In fact, the widespread popularity of Meyer’s Briggs
in business settings and with the general public suggests that an
artificial personality based on the Jungian model may perform
well with respect to convincing other people of the machine’s
personality.
      </p>
      <p>
        Artificial personality synthesis is at a similar point in
development as the airplane was at the time of the Wright
Brothers. You do not need to understand how a bird flies in
order to build a transatlantic aircraft, and you do not need to
understand how the human mind works in order to build a
machine that has a recognizable personality. Finally, it is
interesting to note that while the Jungian perspective on
artificial personality synthesis presented here is very different
from the mainstream views on the topic that center on the use
of Big-5 theory, this paradigm is not any more controversial
than the Freudian paradigm advocated for by Marvin Minsky
[
        <xref ref-type="bibr" rid="ref9">21</xref>
        ]. The Jungian paradigm presented in this work is worth
consideration in future artificial personality synthesis. It is
attractive in the sense that it can leverage a variety of existing
algorithms to implement the personality. It also has the
property that an artificial personality made with this
framework should exhibit the full range of human personality
as described by Jung.
      </p>
    </sec>
    <sec id="sec-14">
      <title>7. ACKNOWLEDGMENTS</title>
      <p>This work was completed under the support of a Los Alamos
National Laboratory Early Career Research Award
#20140629ECR. The concepts presented in this work were
refined with the help of Sebastián A. Zanlongo.</p>
    </sec>
    <sec id="sec-15">
      <title>8. REFERENCES</title>
      <p>[1] A. Vinciarelli and G. Mohammadi, "A Survey of Persoanlity
Computing," IEEE Transactions on Affective Computing,
vol. 5, no. 3, pp. 273-291, June 2014.
[2] C. G. Jung, Psychologische Typen (Psychological Types), 1
ed., Zurich: Rascher Verlag, 1921.
[3] C. Jung, The Portable Jung, J. Cambell, Ed., New York: The</p>
      <p>Viking Press, 1976.
[4] L. V. Berens and D. Nardi, Understanding Yourself and
Others: An Introduction to the Personality Type Code,
Huntington Beach, CA: Telos Publications, August 1, 2004.
[5] The Myers and Briggs Foundation, [Online]. Available:
http://www.myersbriggs.org/my-mbti-personality-type/mbtibasics/sensing-or-intuition.htm. [Accessed 1 June 2015].
[6] The Myers &amp; Briggs Foundation, [Online]. Available:
http://www.myersbriggs.org/my-mbti-personality-type/mbtibasics/thinking-or-feeling.htm. [Accessed 1 June 2015].
[7] The Meyers &amp; Briggs Foundation, [Online]. Available:
http://www.myersbriggs.org/my-mbti-personality-type/mbtibasics/isabel-briggs-myers.htm. [Accessed 1 June 2015].
[8] Center for Applications of Psychological Types, [Online].</p>
      <p>Available:
http://www.capt.org/mbti-assessment/isabelmyers.htm. [Accessed 1 June 2015].
[9] M. Gailliot, R. Baumeister, C. DeWall, J. Maner, E. Plant, D.</p>
      <p>Tice, L. Brewer and B. Schmeichel, "Self-control relies on
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[10] K. Pearson, "On Lines and Planes of Closest Fit to Systems
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[11] L. Nummenmaa, E. Glerean, R. Hari and J. K. Hietanen,
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[12] L. Cunningham, April 13, 2013. [Online]. Available:
http://www.seattletimes.com/business/myers-briggspersonality-test-embraced-by-employers-not-allpsychologists/. [Accessed 1 June 2015].</p>
    </sec>
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