Evolution-Based Personality Theory
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Role of Personality in an Integrated Conception
The multiaxial model of the DSM has been
specifically composed to encourage integrative conceptions of the individual's
manifest clinical symptoms in terms of their place between long-standing
personality styles and current psychosocial stressors. Our task as clinicians
is to understand the preceding interaction in order to achieve a conception
of each patient's psychopathology that does not merely diagnose or document
his or her symptoms, the physical diseases that parallel the Axis I clinical
syndromes, but also contextualizes these symptoms with reference to the
larger context of the individual's personality style of perceiving, thinking,
feeling, and behaving.
The movement toward integrationism in the conception
of disease is both an ideal and an historical fact, illustrated by the
evolution of the health sciences through two recent paradigm shifts, as
The series of concentric circles in the figure above
represent revolutions that have occurred in medicine over the past century.
In the center, we find Axis I, the so-called clinical syndromes, for example,
depression and anxiety. These parallel the state of medicine a hundred
or more years ago, when physicians defined their patients' ailments in
terms of their manifest symptomatology, that is, their sneezes, coughs,
boils and fevers, labeling these "diseases" with terms such as "small
pox," on the basis of their superficial appearance.
The outer ring of the figure parallels Axis IV of
the DSM. The related medical paradigm shift occurred approximately a century
ago when illnesses began to be viewed as the result of intrusive microbes
which infect and disrupt the body's normal functions. In time, medicine
began to assign diagnostic labels to reflect this new etiology, replacing
its old descriptive terms. "Consumption", for example, was retitled "tuberculosis"
to signify the assaulting bacterium.
Medicine progressed further beyond its turn-of-the-century
"infectious disease" model, an advance most striking these last 25 years
owing to immunological science. This progression reflects a growing awareness
of the key role of the immune system, the body's intrinsic capacity to
overcome the omnipresence in life of potentially destructive infectious
and carcinogenic agents that pervade our physical environment. Medicine
learned that it is not the overt symptoms, the sneezes and coughs, nor
the intruding infections, the viruses and bacteria, that are the key to
health or illness. Instead, health and disease were seen to be a function
of the competence of the body's own intrinsic defensive capacities. Millon
asserted in his theory that in psychopathology it is not the overt anxiety
or depression, nor the stressors of childhood or contemporary life that
are the key to psychological well-being. Rather, it is the mind's equivalent
of the body's immune system, that structure and style of psychic processes
that represents our overall capacity to perceive and to cope with our
psychosocial world that is the key determinant of mental health or disorder;
it is, in other words, the psychological structure and function we term
Elements of evolutionary theory were introduced by
Millon in a 1990 book owing to his belief that its essential principles
operate in all aspects of nature and scientific endeavor, from cosmogony,
at one end, to human interactions, at the other. Pathological forms of
human functioning were interpreted by Millon as disruptions or imbalances
in those evolutionary principles that foster the functions of survival
and ecologic adaptation. From this viewpoint, personality maladaptations
could not be fully understood by limiting attention, for example, solely
to cognitive preconceptions, or to unconscious repetition compulsions,
or to neurochemical dysfunctions. rather, each of these psychological
dysfunctions represent a partial expression of evolutionary functions
that have gone awry. Cognitions, unconscious structures, interpersonal
styles, and neurohormonal dynamics were viewed, in this formulation, as
structural forms or functional mechanisms that reflect evolutionary processes.
Each evolutionary structure or function is important in that it serves
to identify one clinical domain in which pathology manifests itself, and
hence becomes one vehicle for specifying and understanding that pathology.
But, each of these manifestations and correlates are not the totality
of pathology, however, but one of several expressions and mechanisms of
problematic evolutionary structure or functions in realms cognitive, behavioral,
affective, as well as biologic.
In his 1990 book, Millon conceptualized the theoretical
grounding of clinically derived personality styles and disorders. As a
result, Millon deduced that the principles and processes of evolution
were universal phenomena, albeit expressed in nature's many realms at
different levels and in different manifest forms. What was gratifying
in this reconceptualization was the close correspondence between his earlier
1969 biosocial-learning theory and the key principles comprising his new
1990 evolutionary model. Additionally satisfying was that the ontogenetic
theory of neuropsychological stages of development presented in 1969 similarly
paralleled his theoretical formulations of evolutionary phylogenesis.
Millon came to believe that the widespread desire
among theorists to unify science should not be limited to explicating
physics; that is, it should be possible in all fields of nature that have
been subdivided by habit, tradition, or pragmatics (e.g., economics, sociology,
geology). He believed unification to be a worthy goal even within the
newer sciences, such as personology. Efforts to coordinate the separate
realms that comprise the study of personality and, more specifically,
that of mental disorders would be particularly useful. Rather than developing
independently and being left to stand as autonomous and largely unconnected
professional activities and goals, a truly mature clinical science of
mental functioning, one that would create a synergistic bond among its
elements, would embody, five explicit elements:
Universal scientific principles are grounded in
the ubiquitous laws of evolutionary theory as found in nature. Despite
their varied forms of expression (cosmology, biology), these principles
may provide an undergirding framework for guiding and constructing numerous
specific and focused subject-oriented theories of nature's structures
Subject-oriented theories, or explanatory and heuristic
conceptual schemas for specific subjects, such as personology and psychopathology.
These theories should be consistent with established knowledge in both
its own and related sciences and should enable reasonable accurate propositions
concerning all clinical conditions to be both deduced and understood,
enabling thereby the development of a formal classification system.
Classification of personality styles and pathological
syndromes, or a taxonomic nosology that has been derived logically from
the subject areas' theory. The taxonomy should provide a cohesive organization
within which its major subject categories can readily be grouped and
differentiated, permitting thereby the development of coordinated assessment
Personality and clinical assessment instruments,
or tools that are empirically grounded and sufficiently sensitive quantitatively
to enable the theory's propositions and hypotheses to be adequately
investigated and evaluated. The clinical categories comprising its nosology
should be able to be readily identified (diagnosed) and measured (dimensionalized),
thus specifying target areas for interventions.
Personalized therapeutic interventions, or planful
strategies and modalities of treatment. These interventions should accord
with the theory and be oriented to modify problematic clinical characteristics,
consonant with an understanding of the whole person being treated.
The table below provides a simple summary of the preceding
five elements, comprising what may be called the science of clinical psychology.
Most theories of the personality disorders have been
developed within a particular and narrow orientation, such as the psychodynamic,
the cognitive, the behavioral, the interpersonal, or the biophysical.
Such theories are incongruent with nature itself, which reflects the patterning
of variables across the entire matrix of the person. To be commensurate
with the construct of personality, a theory must be based on nature's
principles which span, or transcend, each of these multiple domains. Specific
narrow domain approaches confuse part and whole. The principles of evolution
reflect nature's basic functions, and serve to integrate the several domains
that comprise personality.
Philosophers of science agree that it is theory which
provides the conceptual glue that binds a classification nosology together.
Moreover, a good theory not only summarizes and incorporates extant knowledge,
it possesses what they call systematic import, that is, it can originate
and develop entirely new observations and new methods. Such taxonomy must
also "carve nature at its joints," so to speak. The philosopher of science
Carl Hempel (1965) referred to this when he distinguished between natural
and artificial classification systems. As he wrote: "Distinctions
between 'natural' and 'artificial' classifications may well be explicated
as referring to the difference between classifications that are scientifically
fruitful and those that are not: In a classification of the former kind,
those characteristics of the elements which serve as criteria of membership
in a given class are associated, universally or with high-probability,
with more or less extensive clusters of other characteristics. ...a classification
of this sort should be viewed as somehow having objective existence in
nature, as 'carving nature at the joints'... (Aspects of Scientific Explanation,
1965, pp. 146-147). The ideal of a classification scheme which is "natural,"
is one which "inheres" in the subject domain, that is not "imposed" on
it by committee consensus or statistical methodology. Such a system would
be not only be sufficient with respect to the phenomena of a subject domain,
but also logically necessary.
The Polarity Model for Deriving Personality Styles
Millon's theoretical model is grounded in evolutionary theory. In essence,
it seeks to explicate the structure and styles of personality with reference
to deficient, imbalanced, or conflicted modes of survival, ecological
adaptation and reproductive strategy. The proposition that the development
and functions of personologic traits may be usefully explored through
the lens of evolutionary principles has a long, if yet unfulfilled tradition.
Spencer (1870) and Huxley (1870) offered suggestions of this nature shortly
after Darwin's seminal Origins was published. In more recent times, we
have seen the emergence of sociobiology, an interdisciplinary science
that explores the interface between human social functioning and evolutionary
biology (Wilson, 1975, 1978).
Four domains or spheres in which evolutionary principles are demonstrated
have been labeled by Millon as Existence, Adaptation, Replication,
and Abstraction. The first relates the serendipitous transformation of
random or less organized states into those possessing distinct structures
of greater organization; the second refers to homeostatic processes employed
to sustain survival in open ecosystems; the third pertains to reproductive
styles that maximize the diversification and selection of ecologically
effective attributes; and the fourth concerns the emergence of competencies
that foster anticipatory planning and reasoned decision-making. Polarities
from the first three phases have been used by Millon to construct a theoretically-derived
classification system of personality disorders.
Existence: The Pleasure-Pain Polarity.
The first phase, existence, concerns the maintenance of integrative
phenomena, whether nuclear particle, virus, or human being, against the
background of entropic decompensation. Evolutionary mechanisms derived
from this stage regard life-enhancement and life-preservation. The former
are concerned with orienting individuals toward enhancing survival and
improvement in the quality of life; the latter with orienting individuals
away from actions or environments that decrease the quality of life, or
jeopardize existence itself. These may be called existential aims. At
the human level of functioning such aims form, phenomenologically or metaphorically
, a pleasure-pain polarity.
Adaptation: The Active-Passive Polarity.
To exist is but an initial survival phase. Once an
integrative structure exists, it must maintain its existence through exchanges
of energy and information with its environment. The second evolutionary
stage relates to what is termed Modes of Adaptation; it is also framed
as a two-part polarity, a passive orientation, that is a tendency to accommodate
to one's ecological niche, versus an active orientation, that is a tendency
to modify or intervene in one's surrounds. These modes of adaptation differ
from the first phase of evolution, in that they relate to how that which
exists is able to endure or continue to survive in its environment.
Replication: The Self-Other Polarity.
Although organisms may be well-adapted to their environments,
the existence of all life-forms is time-limited. To circumvent this limitation,
organisms have developed Replication Strategies, that is, ways in
which to leave progeny. These strategies reflect what biologists have
referred to as r- or self-propagating strategy, at one polar extreme,
and K- or other-nurturing strategy, at the other extreme. Psychologically,
the former strategy is disposed toward actions which maximize self-reproduction;;
here, organisms are egotistic, insensitive, inconsiderate, and socially
uncaring; while the latter strategy is disposed toward protecting and
sustaining kin or progeny; this leads to actions which are socially affiliative,
intimate, caring, and solicitous.
Deriving Personality Disorders from Theory
Some personalities exhibit a reasonable balance on
one or other of the three preceding polarity pairs. Individual differences
in both personality features and overall style will reflect the relative
positions and strengths of each polarity component. Personalities we have
termed deficient lack the capacity to experience or to enact certain aspects
of one or another of the three polarities (e. g., the schizoid has a faulty
substrate for both "pleasure" and "pain"); those spoken of as imbalanced
lean strongly toward one or another extreme of a polarity (e. g., the
dependent is oriented almost exclusively to receiving nurturance from
"others"); and those we judge conflicted struggle with ambivalences toward
opposing ends of a bipolarity (e. g., the passive-aggressive vacillates
between adhering to the expectancies of "others" versus enacting what
is wished for one's "self'). The table below provides an overall summary
of the derived types and disorders.
A COMPREHENSIVE CHART OF THEORY-DERIVED
Personalities termed pleasure-deficient lack the capacity
to experience or to enact certain aspects of the three polarities. The
interpersonally-imbalanced lean strongly toward one or another extreme
of a polarity. Finally, the intrapsychically-conflicted struggle with
ambivalences toward opposing ends of a bipolarity.
Three additional pathological personality patternsóthe
Schizotypal, Borderline, and Paranoidórepresent structurally-deficient
personalities in the more advanced stages of pathology. Reflecting an
insidious and slow deterioration of the personality structure, these differ
from the basic personality disorders by several criteria, notably, deficits
in social competence and frequent (but usually reversible) psychotic episodes.
Less integrated in terms of personality organization and less effective
in coping than their milder counterparts, they are especially vulnerable
to the everyday strains of life.