Beyond Four Forces: The Evolution of Psychotherapy

One framework for studying the evolution or development of personality theory and psychotherapy is the concept of forces—theoretical models, paradigms, dimensions, movements, or worldviews—that have made significant contributions to and shaped the field. This article describes and documents the rise of this evolutionary construct, the identification of the first three forces of psychotherapy (psychoanalytic, behavioral, and humanistic-existential), and the naming of the fourth force given to several, significant theoretical paradigms (transpersonal psychology, family systems, feminist psychology, multicultural psychology, ecopsychology, and social constructivism and postmodernism). In the past decade, a fifth force (social justice and advocacy) has been widely acknowledged. An integrative, inclusive, and holistic conceptualization of psychotherapy is presented as an emerging sixth force. These evolutionary milestones of the field demonstrate an expanding process that has become increasingly more integrative; a more comprehensive, systemic, and holistic approach is needed to better address diverse individual, community, and global needs.


The First Three Forces Identified in the 1960s
In the preface of his book, Toward a Psychology of Being, Maslow (1962) described an emerging psychological theory as the third force, which he differentiated from the other two dominant psychotherapy paradigms of the time, "the Freudian and the experimental-positivistic-behavioristic" (p. vi). Maslow postulated that the existential-humanistic psychological understanding of human nature offers a more complete understanding of those who are "relatively healthy" (p. 158). Therefore, this may be "another branch of psychology, the psychology of the fully evolved and authentic Self and its ways of being" (pp. 15, 78). In the second edition of this same text, Maslow (1968) wrote a new preface wherein he asserted that "humanistic psychology . . . is now quite solidly established as a viable third alternative . . ." (p. iii). He emphasized that this humanistic understanding of human nature is a new approach not only to psychotherapy but also to many other fields, from business to education (for an excellent history, see DeCarvalho, 1990;Moss, 1999). Other humanistic psychologists agreed that this third force was distinct from the deterministic and positivistic premises of psychoanalysis and behaviorism (Bugental, 1964;Rogers, 1963;Welch, Tate, & Richards, 1978).
Finally, although the field of psychology has changed significantly over the last several decades, the identification of humanistic-existentialism as the third force of psychology and psychotherapy has persisted and includes a strong professional identity, national and international (and other national) professional associations, and scholarly journals. DeRobertis (2013) argued that, although not as influential as it once had been, humanistic psychology is as relevant as ever. Its values inform important developments in the field, including the legitimization of qualitative research and the emerging interest in positive psychology, existential neuroscience, the phenomenology of consciousness, and the creation of meaning through interpersonal interaction. The effectiveness of humanistic-existential therapies has been summarized in several extensive reviews of the research (e.g., Cain, 2016;Cain, Keenan, & Rubin, 2016;Elliot, Greenberg, Watson, Timulak, & Friere, 2013;Lambert, Fidalgo, & Greaves, 2016). Furthermore, the validity of the central theoretical premises of these approaches has been supported by the research on the importance of common factors first emphasized by humanistic approaches (therapeutic alliance, empathy, genuineness) that contribute to positive outcomes (Lambert, 2013a;Messer & Wampold, 2002;Norcross & Wampold, 2011;Wampold, 2001;Watson, 2016).

Transpersonal Psychology
In 1968, Maslow (1968, pp. iii-iv;1969a) proclaimed that the third force in psychology was "transitional, a preparation for a still 'higher' Fourth Psychology, transpersonal, transhuman, centered in the cosmos rather than in human needs and interest, going beyond humanness, identity, self-actualization, and the like." In the same year, Sutich (1968), a founding member of humanistic psychology, pioneered that transpersonal psychology was the "emerging" fourth force in psychology, a field interested in "ultimate human capacities," unlike the other three forces (pp. 77-78). Maslow (1969b) and Assagioli (1969) described and differentiated the attributes of those who are considered to be "normal" from those who develop beyond-normal ways of being, people who are motivated by transpersonal values, and people who have transpersonal traits. These traits include the willingness to descend into the lower realms of human nature to face their darker attributes or "shadow," as they also pursue development into the higher realms of the mind and spirit through engaging in practices that expand consciousness. This process often includes the experience of rebirth or liberation (Assagioli, 1969), as well as a drive to be immersed in humanity (Maslow, 1971), to take responsibility for one's behaviors and to engage selflessly in the world to serve others (Maslow, 1971;Vaughan, 1981). Although not viewed as a primary force by many, transpersonal psychology continues to make contributions to the field through multinational and international associations in over 18 countries, national and international conferences, and professional journals and textbooks that continue to feature transpersonal psychology as one of the foundational theoretical models in the field (e.g., Fadiman & Frager, 2013; for a current description of transpersonal psychology and its history, see M. Daniels, 2013;Friedman & Hartelius, 2013).
Given the purpose of this article, it is important to note that, unlike the first three forces, transpersonal psychology was never identified as one theoretical model guiding one psychotherapeutic approach. The other three forces were remarkably distinct from each other, describing human nature, health, pathology, and psychological treatment in ways that were quite different from the other two forces. Transpersonal psychology was offered as a more expansive way of working with clients across other theoretical models. For example, there are transpersonal-psychodynamic therapists, transpersonal-behavioral therapists, and transpersonal-humanistic therapists (e.g., see Boorstein, 1980). This fourth force is also unique in that it prioritizes the role of (a) consciousness (e.g., Rodrigues & Friedman, 2013), (b) spirituality (Hartelius, Friedman, & Pappas, 2013), and (c) "extreme health and well-being," as well as other experiences mostly ignored by the other three forces, including "altered states of consciousness, peak experiences, self-realization, and meditation and other consciousness-altering techniques" (Walsh & Vaughan, 1980, p. 13). In addition, a couple decades after the inception and development of transpersonal psychology, the positive integration of spirituality and religion into the general framework of psychotherapy and personality theory was finally encouraged (e.g., P. S. Richards & Bergin, 1997;Shafranske, 1996) and has continued to gain support (e.g., American Counseling Association, 2009;Vieten et al., 2016).
Long before mindfulness became popular in the West, the use of meditation in therapy was described by Goleman (1971, p. 4) as "a main route for the newly emergent fourth force." Other mindfulness activities and spiritual practices that aim to enhance awareness and expand consciousness have been central to transpersonal therapies for decades (e.g., Grof, 2012;Rodrigues & Friedman, 2013;Walsh, 2014). Hundreds of empirical studies have documented various health and psychological benefits of engagement in the regular practice of meditation; for a review of this research in the context of transpersonal psychology, see MacDonald, Walsh, and Shapiro (2013); for summaries and discussions of research studies demonstrating the benefits of other interventions commonly used in transpersonal approaches, see Friedman and Hartelius (2013). To their credit, from the 1970s onward, transpersonal psychologists have encouraged a transcultural approach to therapy, one that respects cultural differences and invites collaboration with psychological and spiritual and religious traditions and practices from around the world (Boorstein, 1980;Walsh, 2001;Walsh & Vaughan, 1993; also see Friedman, Krippner, Riebel, & Johnson, 2010). Thus, in essence, this perspective is a transcultural and transtheoretical or metatheoretical ideology and approach to therapy.

Family Systems Psychology
In the 1950s, general systems theory (von Bertalanffy, 1968), viewed by many as a "revolution in scientific thought" (e.g., Steinglass, 1978, p. 301), was integrated into the newly emerging practice of family therapy. This systemic theoretical approach became increasingly popular in the 1970s and 1980s, when it was pronounced the fourth force in the field (Broderick & Schrader, 1981;L'Abate, 2013). L'Abate (1985) explained that, in the middle of the 20th century, psychotherapists were unprepared to work with families, even though family life and relationships are critical to human existence and well-being. He emphasized the significant clinical difference between the linear focus on an individual and a "circular, contextual, and dialectical" focus on families (p. xi). In 1998, Becvar and Becvar proposed that secondorder cybernetic systems theory, particularly as applied to family therapy, represented a paradigm shift in the field of psychology and psychiatry. Unlike previous paradigms, this approach provided a postmodern understanding of humans who live in their own social and cultural constructions that are co-created and shared with others, systemically through mutual interaction. By the end of the century, systemic relationship therapy had become mainstream, with its own international professional identity, journals, societies, state licensure, and university curricula (Becvar & Becvar, 1998Goldenberg & Goldenberg, 2009;McGoldrick, Carter, & Garcia-Preto, 2011). Although there are several classical family therapy theoretical models (e.g., structural, strategic, and experiential), systemic family therapy is similar to other fourth force approaches in that it is also metatheoretical and has been integrated with many single-school approaches (e.g., Nichols, 2017).
Over the last few decades, empirical evidence has demonstrated the validity of family and couples' assessment tools, as well as the effectiveness and efficacy of a systemic interventions, in general (e.g., for summaries of this research, see Becvar & Becvar, 2013;Goldenberg & Goldenberg, 2009;Nichols, 2017;Sprenkle, 2012; for a wide range of specific child-and parent-related concerns, see Becvar & Becvar, 2013;Couturier, Kimber, & Szatmari, 2013;Tanner-Smith, Jo Wilson, & Lipsey, 2013;Vermeulen-Smit, Verdurmen, & Engels, 2015). L'Abate (2013) has continued to emphasize the importance of this "paradigm as the fourth force in psychological theories" (p. 5). Becvar and Becvar (2013) reaffirmed that second-order cybernetics is "a metaperspective" that validates many perspectives and "embraces an ethical imperative to act in a manner that participates in the creation of a more humane reality" (p. xviii).

Feminist Psychology
In the late 1960s and 1970s, an influential group of women and feminist scholars issued scathing critiques of the field of psychology as a whole and of the primary schools of psychotherapy: A radical transformation of psychology was needed (e.g., Broverman, Broverman, Clarkson, Rosenkrantz, & Vogel, 1970;Chesler, 1972;Hare-Mustin, 1980;Parlee, 1979;Weisstein, 1968). These feminists illustrated how the traditional personality theories, diagnostic categories, and even so-called objective research methods were grounded in a limited worldview of a White, upper-middle-class, heterosexist patriarchy that ignored the tremendous influence of sexism, gender roles, social class, race, oppression, privilege, and power on identity development and psychological health. They pushed the field of psychology to look beyond the intrapsychic, behavioral, and androcentric self-actualizing nature of the individual and beyond the dynamics of the family system to the sociopolitical systems that legitimized social contexts that are oppressive to those with less power. In essence, they pressed therapists, theorists, and researchers to realize that they had all been encased in the perspective of a socially constructed dysfunctional mega-system (e.g., L. S. Brown, 1994;Comas-Díaz, 1991Comas-Díaz & Greene, 1994;Enns, 1993Enns, , 2004Gilligan, 1982;Hare-Mustin & Marecek, 1990;Inman & O'Shaughnessy, 2013;Silverstein, 2006;Williams & Barber, 2004).
By the late 1970s, new and revised models of psychotherapy that integrated feminist principles and values were developed, including nonsexist psychotherapy, assertiveness training, and social action that prioritized systemic change through consciousness raising and a redistribution of social and political power (e.g., Rawlings & Carter, 1977; also see J. Daniels, 2007;Enns, 1993Enns, , 2004Enns, Williams, & Fassinger, 2012;Greenspan, 1983;Miller, 1986). By the 1990s, feminist psychology was identified as one of the fourth forces in psychology (Ivey, 1993;Ivey & Rigazio-DiGilio, 1992). In fact, Ivey (1993), among others, described the emerging fourth force as both feminist and multicultural psychology (J. Daniels, 2007;Pedersen, 1990Pedersen, , 1991. He urged all scholars and practitioners to become gender-fair and to revise the patriarchal theories of the autonomous self that lacked a consideration of the self in relation to others and to community. Many others agreed, asserting that the advances in social justice and advocacy for historically oppressed groups should be attributed, at least in part, to the persistent work and scholarship of feminist activists (e.g., L. S. Brown, 1994Brown, , 2010Comas-Díaz, 1991Comas-Díaz & Greene, 1994;Goodman et al., 2004;Inman & O'Shaughnessy, 2013;Silverstein, 2006).
According to L. S. Brown (2010), it has been difficult to assess the effects of the specific components of feminist psychotherapy, given that feminist therapies and interventions are integrated into a wide range of theoretical models and modalities. Nonetheless, reviewers of research have critically examined the core components of feminist therapies and have affirmed consistently positive outcomes, overall, and specifically in the areas of (a) empowerment of the oppressed, (b) critical consciousness development, (c) reappraisal of gender roles and social identity, (d) resocialization, and (e) social activism (e.g., L. S. Brown, 2010;Enns, 1993Enns, , 2004Enns & Byars-Winston, 2010). Feminist multiculturalists continue to make critical contributions to the evolution of psychotherapy and psychology, especially as the field acknowledges the importance of social justice as integral to health and well-being (e.g., L. S. Brown, 2010;Comas-Díaz & Greene, 1994;Enns et al., 2012;Inman & O'Shaughnessy, 2013).

Multicultural Counseling and Psychology
In the 1950s and 1960s, the civil rights movements in the United States ignited social changes that strengthened academic interest in gender, racial, ethnic, and diversity psychology and identity development, as well as in the negative effects of prejudice, oppression, and victimization. Psychotherapists and academics gradually began to confront and address the lack of cultural awareness and expertise in their clinical practice, theoretical models, and research strategies. By the 1970s, many began to challenge the field to examine how current personality theories and counseling models were limited, inadequate, inaccurate, and often harmful, especially given that Western values framed the definition of mental health and perpetuated the assumption that internal factors accounted for personal deficiencies (e.g., Arredondo-Dowd & Gonsalves, 1980;Atkinson, Morten, & Sue, 1979;Ivey, 1973;Pedersen, 1974Pedersen, , 1983P. M. Smith, 1971;Sue, 1978). Gradually, a mandate was established that all counselors and psychologists (a) become culturally selfaware; (b) gain the values, knowledge, and skills that demonstrate respect for human differences; (c) use culturally relevant and adaptive interventions, when appropriate; (d) and seek knowledge about the prevalence and impact of oppression and privilege on the health and well-being of diverse populations (e.g., Atkinson & Israel, 2003;Comas-Díaz, 1991Arredondo & Perez, 2003;Arredondo & Tovar-Blank, 2014;Goodman et al., 2004;Ivey, 1993; C. C. Lee, 1998;Pedersen, 1990Pedersen, , 1991Pedersen, , 1999aSue et al., 1982;Sue et al., 1998;Sue, Ivey, & Pedersen, 1996;Sue & Sue, 1981Toporek, Gerstein, Fouad, Roysircar, & Israel, 2006;Vera & Speight, 2003).
Through years of persistence and the advocacy of many, the American Psychological Association (1981,1990,2000,2003,2007,2018) acknowledged the ethical responsibility of psychotherapists and researchers to gain awareness, knowledge, and skills to work with diverse people; in this context, diversity included culture, ethnicity, race, religion, gender, sexual orientation and gender identity, age, ability, and economic class (Arredondo & Perez, 2003;Ivey & Collins, 2003;Sue, Arredondo, & McDavis, 1992;Sue et al., 1982). The American Counseling Association followed suit (Arredondo & Perez, 2003;Ivey & Collins, 2003;Ratts, Singh, Nassar-McMillan, Butler, & McCullough, 2016;Sue et al., 1992). An increasing emphasis was placed on educating and training graduate students to be "culturally effective" and to engage in advocacy roles (Arredondo-Dowd & Gonsalves, 1980;Pedersen, 1974Pedersen, , 1978Ponterotto & Casas, 1987;Sue, 1978a;Sue et al., 1982). Multicultural and ethical guidelines and competencies were developed, revised, and codified, by both the American Psychological Association (1990) and the American Counseling Association (Ratts et al., 2016;Sue et al., 1992), throughout the end of the 20th and into the 21st century, in an effort "to eliminate biases, prejudices, and discriminatory practices" among psychologists and counselors (American Psychological Association, 1990, Guideline 8). These standards were designed to aid counselors and those in training to address personal and institutional racism, as well as to engage in more culturally relevant and meaningful therapy with diverse clients (Arredondo, 1999).
By the turn of the century, a paradigm shift in counseling and psychology was in full force (Ivey, 1993;Pedersen, 1991Pedersen, , 1999aPedersen, , 1999b. All theoretical approaches needed to be revised to address a more complete, complex, and dynamic understanding of human nature-to include social and environmental contextualism and specifically the impact of culture and diversity broadly defined (Pedersen, 1990(Pedersen, , 1991(Pedersen, ,1999a(Pedersen, , 1999b. Multiculturalism must inform all psychological theory development and refinement, research and assessment tools, and application through psychotherapy, community service, and education policies and licensure standards (e.g., Quintana, Chew, & Schell, 2012;Sue et al., 1996). This new paradigm included the critical importance of culture, race, ethnicity, immigration, acculturation, enculturation, language, religion, sexual and gender identities, differing abilities, and so forth on core identity development; it emphasized an examination of the sociopolitical factors that perpetuate prejudice, discrimination, oppression, and privilege and the psychological consequences of oppression, poverty, and classism-based and race-based trauma (e.g., Carter, 2007; D. R. Fox & Prilleltensky, 2009;Goodman et al., 2004;Liu, 2011Liu, , 2013Mirowsky & Ross, 2003;Nurius, Uehara, & Zatzick, 2013;Quintana et al., 2012;L. Smith & Mao, 2012). Pedersen (1990Pedersen ( , 1991Pedersen ( , 1999a may have been the first to articulate that the profession was "moving toward a generic (and perhaps even grand) theory of multiculturalism as a 'fourth force' position" (Pedersen, 1991, p. 6). Others agreed (e.g., Arredondo & Tovar-Blank, 2014;J. Daniels, 2007;Essandoh, 1996;Ivey, 1993;Lewis & Arnold, 1998;Ponterotto & Casas, 1991). Social scientists and counselors can only begin to understand, assess, and assist others given a culture-centered perspective (Pedersen, 1999a). This newly recognized fourth force was not intended to displace the first three, but "rather to complement them by framing them in the cultural contexts" (Pedersen, 1999a, p. 4). This grand conceptual framework was being shaped through much dialogue and debate in the field and beyond (Pedersen, 1983(Pedersen, , 1991(Pedersen, , 1999bSue et al., 1998). Sue and colleagues (1998;Sue et al., 1982) emphasized a postmodern definition of multiculturalism that acknowledged the coexistence of multiple socially constructed worldviews, cultural norms, and values. Multicultural competence, according to these authors, includes diversity broadly defined (i.e., socioeconomic status, gender, sexual orientation and identity, abilities/disabilities, and so forth), in addition to race, ethnicity, multiracial, and multi-heritage identities. Therefore, multiculturalism as a fourth force in psychology is described as a metatheory and praxis with an organizing framework that is more integrative and holistic; it must be applied at the individual, group, and universal levels (Comas-Díaz, 1994; C. C. Lee, 2007Lee, , 2012Pedersen, 1990Pedersen, , 1999aPedersen, , 1999bRatts & Pedersen, 2014;Sue et al., 1996).

Ecopsychology
Numerous environmental movements arose in the mid-1960s through the 1980s (e.g., deep ecology, ecofeminism, bioregionalism, and environmental justice) to challenge political, corporate, and government policies and practices that mechanized, commercialized, and devalued nature (e.g., Carlson, 1962;W. Fox, 1990;Merchant, 1980;Plant, 1989). The behavioral sciences were also subject to criticism. L. R. Brown (1995) summoned psychologists to acknowledge that human sanity requires an emotional relationship with and deep valuing of the natural environment. Multidisciplinary theorists traced the changing interrelationship that humans have had with nature over the millennia and the negative impact that humanity's increasing separation from nature has had on the environment and on the human psyche (e.g., Diamond & Orenstein, 1990;M. Fox, 1988;Rosak, 1992;Shepard, 1982).
By the end of the 20th century, ecopsychologists selfidentified themselves and called for a revisioning of psychology that included the essential nature of humans as inextricably interconnected with the natural world (e.g., Clinebell, 1996;Conn, 1995Conn, , 1998Mack, 1992;Metzner, 1995Metzner, , 1999Rosak, 1992Rosak, , 1995Rosak et al., 1995). They contended that the health of the ecosystem and the well-being of the human species are synergistically interrelated (e.g., Conn, 1995Conn, , 1998Kahn & Hasbach, 2012). Most ecopsychologists have been as concerned about human values and behaviors that have led to the deterioration of the earth's ecology as they have been about the physical and mental health risks associated with people's decreasing respect for the natural world (e.g., Fisher, 2009;Macy, 2007;Metzner, 1995Metzner, , 1999Rosak et al., 1995). Although ecopsychology was not recognized as a fourth force, it was presented as an "enlarged paradigm" because it is an "ecologically grounded theory of personality development" paired with interventions that promote "ecobonding" and a greater love and responsibility for nature (Clinebell, 1996, pp. 25-26, 33-34).
Empirical evidence suggests that humans who lack a conscious and fond relationship with nature suffer negative psychological consequences, including anxiety, depression, and a greater sense of meaninglessness (e.g., Capaldi et al., 2017;Chalquist, 2009;Fisher, 2009;Louv, 2005Louv, , 2012Metzner, 1995Metzner, , 1999Rosak, 1992). Studies have found that human health may be enhanced through contact with nature (plants, animals, natural landscapes, and wilderness; e.g., Frumkin, 2012;Hasbach, 2012;Ingulli & Lindbloom, 2013;Kahn & Hasbach, 2012). Furthermore, the use of ecotherapy or nature-engaged therapies may improve overall mental and physical health; the benefits of spending time in nature include elevated mood, reduced stress, improved immune system, enhanced selfesteem, and increased vitality (e.g., Chalquist, 2009;Frumkin, 2012;Greenway, 2009;Ingulli & Lindbloom, 2013;Trigwell, Francis, & Bagot, 2014;Wilson et al., 2010). In his popular books, Louv (2005Louv ( , 2012 summarized the research to emphasize how healthy childhood development requires direct involvement in nature. Similar to several other proposed fourth forces, ecotherapy was not developed to be a singular theoretical approach to therapy; rather, it is readily integrated into a wide range of therapeutic approaches (e.g., Tudor, 2013). O'Conner (1995) encouraged psychotherapists to accept a new professional ethic in their clinical work that includes and addresses the reality of and responsibility for the global environmental crisis. Manning and Amel (2014) contended that environmental justice is inseparable from social justice in that all people deserve to have access to nature, in their day-to-day lives, as well as to clean air and water. Psychology is inadequate unless it includes and addresses the fundamental needs and rights of humans to be in relationship with nature and the critical importance of a healthy natural environment to support the overall well-being of all living species (Conn, 1995;Rosak, 1995). Psychotherapists and behavioral scientists are urged to recognize the importance of nature on mental and physical health and to be advocates for earth justice; this includes engaging in social action to reduce human behaviors that contribute to the multiple environmental crises (e.g., Masuda, Poland, & Baxter, 2010), many of which adversely affect human health. Comprehensive psychological, sociopolitical, and spiritual approaches are needed to address this crisis (e.g., Buzzell & Chalquist, 2009;Trigwell et al., 2014).

Social Constructivism and Postmodernism
Social constructivism, a popular postmodern worldview, has been identified as a fourth force in psychology and one that has had a significant impact on the field (Jones- Smith, 2012). The theory is grounded in the assumption that, although reality exists, truth, or anyone's perception of the truth about reality, is relative and rooted in the multilayered context of an individual. This context includes history, culture and religion, relationships, language, and the natural world. Personality is not determined by biomechanisms or internal intrapsychic drives, as much as it is constructed by individuals, collectively with others, through their relational processes and given their shared context. Social constructivists have challenged the psychological and ontological understandings of the idealized, autonomous self and have proposed revised constructs of individual freedom and responsibility through the contextual lens of this historical and relational co-construction process (Burr, 1995;D'Andrea, 2000;K. J. Gergen, 1985K. J. Gergen, , 2009) Many personality traits and emotions believed to be inherent or essential to human nature are also reframed as social constructions. From this perspective, gender is socially constructed, as are race, power, and privilege (e.g., S. N. Davis & Gergen, 1997;Hare-Mustin & Marecek, 1990;Weisstein, 1968).
In the mid-20th century, Kelly (1955) introduced personal constructivism to the field of personality theory, postulating that people construe their own sense of themselves and of their world. Self-constructions, informed by socially and culturally constructed systems, are formulated at a very young age and help people to make sense of their lives and to predict outcomes of behaviors. Informed by personal construct theory, therapists attempt to understand their clients' unique personal worldviews and to assess what may and may not be helpful, psychologically sound, or socially moral. Using eclectic techniques, these therapists aim to assist clients to engage in a reconstruction of their own personality and/or of their worldviews such that they can be more productive or content in their day-to-day lives.
In her counseling and psychotherapy theories textbook, Jones-Smith (2012) identified both social constructivism and postmodernism as the fourth force in psychology. She stated that multiculturalism, while tremendously important and something that she has integrated into every chapter of her text, is subsumed under this larger rubric (pp. 3, 8). A few of the primary principles of postmodern therapy are as follows: (a) clients are the experts; (b) therapists are to work collaboratively with clients to empower them to accept responsibility for their actions; and (c) the focus of therapy is on clients' strengths, not on their problems or on what they lack (p. 290). In his textbook on theories of counseling and psychotherapy, Corey (2017) described the postmodern movement as an important "paradigm shift most likely to affect the field" (p. 369); under this domain, he included solutionfocused and narrative therapies.
The evidence for the effectiveness of postmodern approaches is building. Meta-analyses and systematic reviews of the results of numerous studies examining the efficacy of solution-focused brief therapy have shown small but positive results, and other reviews of research are optimistic (Franklin, Trepper, Gingerich, & McCollum, 2012;Kim, 2008). Similarly, although empirical investigations of narrative therapy are less common, they tend to demonstrate its effectiveness (Combs & Freedman, 2012;Etchison & Kleist, 2000;Lopes et al., 2014). Pedersen (1999a), who had proposed that multicultural counseling was the fourth force in 1990, mentioned that others had also proposed a fourth force in the field, such as transpersonal psychology, feminism, and social constructivism. Themes that he had identified in these postmodern fourth forces include (a) a greater tolerance of ambiguity, (b) more emphasis on subjectivity, (c) an appreciation of nonlinear dynamics, (d) the recognition of multidimensional truths, and (e) the value of qualitative research methods. This collective "new paradigm," according to Pedersen, offered to transform the field, from a monocultural perspective, representing the views of the dominant culture, to a multicultural perspective, broadly defined, including all elements of difference that shape human experience and identity (also see Ratts & Pedersen, 2014, Chapter 2). The field of psychology appears to be evolving from one that prioritized objectivity and reductionism and defined human behavior, health, and pathology with primarily intrapersonal descriptors to one that has become increasingly systemic, subjective, contextual, holistic, and nuanced (with a greater focus on diversity, culture, language, symbols, and discourse, as well as more emphasis on each client's needs and preferences). These developments have led to the identification of two additional forces as significant paradigm shifts in psychotherapy: social justice and an integrative, inclusive, and holistic approach to psychology and mental health care.

Social Justice: The Fifth Force
When a psychotherapy paradigm is identified in a public forum as new force, it is not unusual for the proposal to be debated as to whether or not the trend, model, or worldview merits this stature. In some cases, detractors argue that the newly proposed force is not significantly distinct from a previously identified force. For example, this was the case with transpersonal psychology. Some psychologists contended that transpersonal, religious, and spiritual values, needs, and peak experiences were already included under the rubric of humanistic psychology, the third force (e.g., May, 1986;Swartz, 1969). A similar debate ensued when social justice and advocacy were first identified as a fifth force. Some scholars claimed that multicultural counseling (a fourth force) already emphasized justice, equity, and advocacy (e.g., Arredondo & Perez, 2003). Nonetheless, sufficient distinctions were made, and the field of counseling and psychotherapy rather quickly supported the movement to identify social justice as the new prevailing paradigm or fifth force in the field (Ratts, 2009;Ratts et al., 2010;Ratts et al., 2016;Ratts & Pedersen, 2014).
The field of counseling psychology is rooted in sociopolitical reform movements. Its mission has been to enhance the well-being and human dignity of many as well as to increase human rights, justice, and equal access to quality education, vocations, and health care (e.g., Aldarondo, 2007;Goodman et al., 2004;Ivey & Collins, 2003;Kiselica & Robinson, 2001; C. C. Lee, 1998;Prilleltensky, 1994Prilleltensky, , 1999Prilleltensky, , 2001Prilleltensky & Nelson, 1997, 2002. Nonetheless, traditional Western counseling theories and practices viewed individuals primarily through an intrapsychic and apolitical lens; client problems and challenges were assumed to be a function of biological, psychodynamic, emotional, cognitive, and/or behavioral deficits. Psychotherapists of various theoretical orientations focused on assisting clients to create meaningful lives for themselves as they often remained in an unjust social environment that limited their opportunities for optimal mental health and wellness. For the most part, until the rise of feminism and multiculturalism, psychology and counseling had been silent about the deleterious effects of sociopolitical and economic inequity and cultural oppression on the mental and interpersonal health of millions (e.g., L. S. Brown, 1994;Enns, 1993;Ivey, 1993;Prilleltensky, 1994;Sue et al., 1992).
By the end of the 20th century, psychotherapists were warned that they may be inadvertently perpetuating systemic oppression of their clients by providing one-on-one remediation therapy; they were challenged to revise their theoretical models and to engage in prevention, client empowerment, advocacy, and social action (e.g., Martin-Baró, 1994;Prilleltensky, 1999Prilleltensky, , 2001Prilleltensky & Nelson, 1997). Counseling professionals began to realize that their clinical work may do more harm than good unless they better understood the systemic causes of many psychological problems and challenged the injustice inherent in social systems that perpetuated the oppression and marginalization of most people (e.g., Collison et al., 1998;C. C. Lee, 1998;McWhirter, 1997). Psychologists and psychotherapists needed to understand the effects of sociopolitical oppression on human development and to actively work to eradicate societal injustices that limited opportunities to live well. Thus, the constructs of social justice, oppression, unearned privilege, power, and equity began to be centralized in psychological curricula, theories, research studies, and practice models (e.g., Arredondo et al., 1996;Goodman et al., 2004;Helms, 2003;Ivey & Collins, 2003;Kiselica, 2004;C. C. Lee, 1998C. C. Lee, , 2007Lewis & Arnold, 1998;Prilleltensky & Nelson, 2002Sue et al., 1998;Vera & Speight, 2003. Furthermore, a growing body of empirical evidence made it increasingly apparent that human development, health, and pathology can only be understood given individuals' political, social, and economic as well as cultural contexts. Research substantiated that, for most people, healthy intrapsychic development requires a perceptively equitable, fair, and safe sociopolitical environment (e.g., Bryant-Davis & Ocampo, 2005;Carter, 2007;Draine, 2013;Hudson, 2005;Inman & O'Shaughnessy, 2013;Liu, 2011Liu, , 2013Liu & Estrada-Hernández, 2010;Mani, Mullainathan, Shafir, & Zhao, 2013;Mirowsky & Ross, 2003;Nurius et al., 2013;L. Smith & Mao, 2012;Toporek, 2013). Consequently, by the 21st century, an ethical and moral imperative was issued for all mental health counselors and psychologists to work proactively to enhance the well-being of everyone. Psychotherapists were called upon to work for justice and to help end racism, sexism, classism, heterosexism, and other forms of oppression. Integrating social justice into the core of psychotherapy gained increasing support from many (e.g., Arfken & Yen, 2014;Chang, Crethar, & Ratts, 2010;Chung & Bemak, 2012;D'Andrea & Daniels, 2010;Fouad & Prince, 2012;Lewis, Lewis, Daniels, & D'Andrea, 2011;Ratts, 2009;Ratts et al., 2010;Toporek et al., 2006).
A major shift in the field occurred. Counseling professionals responded by redefining their moral and ethical responsibilities to be more politically and socially engaged in institutional, community, societal, and global prevention and intervention (e.g., American Counseling Association, 2005a, 2005bAmerican Psychological Association, 2000, 2003Herlily & Watson, 2007;C. C. Lee, 2007C. C. Lee, , 2012Vera & Speight, 2007). Furthermore, they began to centralize the sociopolitical implications of oppression and of social justice into clinical theory, practice, ethics, and research methods (e.g., Arfken & Yen, 2014;D. R. Fox & Prilleltensky, 2009;Goodman et al., 2004;Liu, 2011Liu, , 2013Lyons et al., 2013;Prilleltensky, Dokecki, Frieden, & Ota Wang, 2007). Numerous intervention models of integrative social justice counseling, empowerment, and advocacy have been proposed, and many have been implemented in diverse settings (e.g., Chung & Bemak, 2012;D'Andrea & Daniels, 2010;Liu, 2013;Ratts et al., 2010;Ratts & Pedersen, 2014;Toporek et al., 2006). Ratts and colleagues (2004, p. 28;Ratts, 2009) are credited with being the first to announce that social justice counseling is the "fifth force" and "a new paradigm. . . emerging in the counseling profession." Others agreed (e.g., Chung & Bemak, 2012;Goodman et al., 2004;C. C. Lee & Hipolito-Delgado, 2007;M. A. Lee, Smith, & Henry, 2013), and the revised Multicultural and Social Justice Competencies were endorsed by American Counseling Association Governing Counseling in 2015 (Ratts et al., 2016). Now that counselors better understand how social oppression and the misuse of privilege diminish mental health, they realize that they may be more effective by engaging in social action and advocacy to help ensure human rights and a more fair distribution of power, resources, and opportunities. Rather than replacing the other forces, the fifth force complements them (e.g., Goodman et al., 2004;Lewis & Arnold, 1998). Ratts et al. (2004) concluded that counselors "must develop more proactive, value-laden, politically conscious, and advocacy-based counseling interventions" (p. 30).
This recently strengthened paradigm represents a primary shift in several areas. It affects counseling professionals' knowledge, identity, roles, ethics, and skills (e.g., Chung & Bemak, 2012;Goodman et al., 2004;Herlily & Watson, 2007;Kiselica, 2004; C. C. Lee & Hipolito-Delgado, 2007;Ratts, 2009;S. D. Smith, Reynolds, & Rovnak, 2009). It is distinct from traditional models of psychotherapy in that the etiology of mental illness is viewed as rooted in social dysfunction rather than as primarily due to internal personal deficits or narratives. This assumption requires knowledge and understanding of the politics of power, including the oppressive power of injustice and the liberating power of social justice (Albee & Joffe, 2004;M. A. Lee et al., 2013;McWhirter, 1997;Prilleltensky, 2008Prilleltensky, , 2012bPrilleltensky, , 2013Williams & Barber, 2004). Furthermore, these changes have required revisions to counseling psychology and counselor education curricula and training opportunities (e.g., Chang et al., 2010;Goodman et al., 2004;Ivey & Collins, 2003;Kiselica, 2004;Ratts et al., 2010;Vera & Speight, 2007). Consequently, in 2009, the Council for Accreditation of Counseling and Related Educational Programs released its revised standards for the accreditation of master's and doctoral degree programs in counselor education to put more emphasis on social justice.
Finally, when social justice scholars contemplate the future, they encourage counseling professionals to become globally literate (e.g., Borgen, 2007;Glover & Friedman, 2015;C. C. Lee, 1998C. C. Lee, , 2007C. C. Lee, , 2012Ng & Noonan, 2012;Prilleltensky, 2012a;van de Vijver, 2013). Global trends affect local communities, and events in local communities (schools, colleges, villages, and cities) affect nations. Critical events that may impede the well-being of many include climate change; the lack of precious resources like water; epidemics spread easily through modern transportation and commerce; financial, international, and political instability; and harmful technologies, to mention a few. C. C. Lee (2012) emphasized the importance of framing human development and mental health from an international perspective.
Transculturally competent counselors and researchers must be guided by social justice values, be informed by global diversity, and work collaboratively across nations (Glover & Friedman, 2015).

Integrative, Integral, and Comprehensive Holistic Approaches: A Sixth Force?
The last force to be addressed in this article is a integrative, holistic, inclusive approach, one that includes the best aspects of the other forces and of other significant developments in the field not commonly identified as a "force" (e.g., evidence-based practice, community psychology, psychoneuroimmunology, positive psychology and psychiatry, emotion-focused or emotionally focused therapy, attachment-based therapies, mindfulness, expressive arts, and neuropsychotherapies). We affirm that a more comprehensive and holistic integrative approach is a sixth or significant force that warrants more emphasis and appreciation as an important paradigm shift in the field (e.g., Friedlander et al., 2012;Ivey & Rigazio-DiGilio, 1992;Norcross & Beutler, 2014;Norcross & Newman, 2003;Sarris et al., 2014).
Although mental health professionals have been intrigued by the idea of integrating single-school psychotherapies since the 1930s, integrative approaches began gaining favor as legitimate models of therapy in the 1970s (Goldfried & Newman, 2003;Norcross & Beutler, 2014;Norcross, Hedges, & Prochaska, 2002;Patterson, 1985). In 1980, Jordaan and Jordaan proposed an integrative metatheory that they claimed to be the sixth force in psychology. Mahoney and Patterson (1992) assessed the development of the four theoretical forces and described the international "convergence movement" as the most recent force; they emphasized the growing attention to the importance of meaning-making, diversity, complexity, social systems, holistic considerations, and quality human relationships to support change. Norcross and Beutler (2014) have been leading advocates of the flexible use of integrative psychotherapies for many years; they contend that outcome research (focused on mechanisms of change) and clients' specific needs and characteristics should guide clinical practice, rather than single-school theoretical approaches. Recently, Friedlander and colleagues (2012) described integrative psychotherapy as the fifth of the five major trends in the field of psychotherapy: (a) psychoanalytic and psychodynamic theories; (b) humanistic and existential therapies, including existentialism, motivational interviewing, and emotion-focused therapy; (c) cognitivebehavioral therapies (from behavioral modification to rational-emotive behavior therapy, cognitive therapy, and multimodal therapy, to personal construct therapy and postmodern constructivism, to dialectical and behavioral therapy and acceptance and commitment therapy); (d) family systems therapy; and (e) psychotherapy integration. These authors supported modern applications of integrative psychotherapies, given the "contextual factors" of the client, which they described as the "problems in living" (e.g., trauma to race-related stress), client characteristics (gender and minority group status), development and resilience (attachment style and spirituality), and the therapeutic relationship (pp. 43-50).
The primary catalysts of the integrative psychotherapy movement include (a) a general decline in polarized debates across theoretical systems, (b) an intensive reappraisal of existing theoretical approaches, (c) an emerging recognition of the value of other schools of thought, (d) a transtheoretical conception of the process of behavioral change (Prochaska, DiClemente, & Norcross, 1992;Prochaska, Johnson, & Lee, 2009), (e) empirical evidence documenting the critical importance of common factors such as empathy and therapeutic alliance (Norcross & Wampold, 2011;Wampold, 2001), and (f) an increasing trend to tailor clinical interventions to include clients ' needs, preferences, and cultural worldviews (American Psychological Association, 2006;Comas-Díaz, 1994;Duncan, Miller, Wampold, & Hubble, 2010;Norcross & Beutler, 2014;Norcross & Newman, 2003). Furthermore, hundreds of empirical outcome studies, including extensive meta-analyses, have failed to demonstrate the consistent superiority of one theoretical approach over the others (Duncan et al., 2010;Lambert, 2013a;Norcross & Wampold, 2011;Wampold, 2001).
Particularly significant to formalizing the integrative psychotherapy movement was the creation of the Society for the Exploration of Psychotherapy Integration (SEPI; n.d.), founded in 1983, and its Journal of Psychotherapy Integration (Goldfried & Newman, 2003). The inception of SEPI fostered enhanced dialogue among a growing number of therapists and researchers of disparate theoretical orientations (Norcross & Goldfried, 2003). In sum, the first decade of intensive investigation into integrative approaches yielded several journals, professional conferences, 200+ peerreviewed publications, and two comprehensive handbooks (Norcross & Goldfried, 2003;Stricker & Gold, 1993). Ultimately, the goal of the movement-its great ambition and creativity notwithstanding-was to "promote the exploration and development of approaches to psychotherapy that integrate across theoretical orientations, clinical practices, and diverse methods of inquiry" (SEPI, n.d., p. 3) to increase the overall effectiveness of clinical interventions (Norcross & Beutler, 2014).
In addition to the integration across clinical approaches to enhance treatment, another equally important change is emerging. There is a growing trend to conceptualize clients and their care from a more holistic and systemically comprehensive perspective, with a greater focus on prevention, overall health, and wellness (e.g., American Psychological Association, 2014; Ivey et al., 2012;Lake, 2009;Lewis et al., 2011;Melchert, 2015;Sarris et al., 2014;Walsh, 2011). Promotion of a clinical approach that includes an emphasis on physical health, spiritual-existential development, and interpersonal-sociocultural well-being has been promoted for two or three decades (e.g., Lazarus, 1973;Sweeney & Witmer, 1991;Vaughan, 1986;Walsh, 2011;Wilber, 1995Wilber, , 2000Wilber, , 2006. However, holistic wellness has not been central to most integrative theoretical models (e.g., Corey, 2011).
Ivey and colleagues (Ivey et al., 2012;Ivey & Rigazio-DiGilio, 1992) proposed that a metatheoretical, multiperspective approach to counseling, one that integrates moral and spiritual growth as well as cognitive, behavioral, and emotional development across the lifespan, is "a growing paradigm shift in the field" (Ivey & Rigazio-DiGilio, 1992, p. 39). They argued, This paradigm shift will extend well beyond traditional psychodynamic, cognitive-behavioral, and existential-humanistic views of counseling and therapy, but in this extension, these traditional theories will retain their vitality and importance. What will be different in the future is that when the old question "What is your theoretical orientation?" is asked, the new answers are going to be developmental, constructivist, multicultural, and systemic-contextual . . . . a more holistic and complete model of therapy and counseling that will be congruent with fourth force orientations. (pp. 39-40) A metatheoretical framework that is more holistic would include an ecosystemic, biopsychosocial, and spiritual, religious, and existential view of the individual, as well as a social justice understanding of mental health.
One of the most comprehensive, holistic, and visionary examples of theoretical integration is integral metatheory, developed by Ken Wilber (e.g., 1995Wilber (e.g., , 2000Wilber (e.g., , 2006. The integral framework provides therapists with a more comprehensive way to enable a greater understanding of human existence and development and of the psychotherapeutic process, including social justice practices. It provides a conceptual map that supports the functionality of a complex, ecosystemic, multidimensional, and multilevel approach that is, by nature, more inclusive than other integrative and holistic models that have been proposed thus far. Ivey and colleagues (2012) promoted the use of integral theory as a "comprehensive framework that represents a pioneering effort to synthesize the tremendous amount of information that currently exists in counseling and psychology" (p. xxiii), as well as in many other important disciplines relevant to the field.
Primarily, the integral metatheory includes five basic features-quadrants, stages (levels), lines, states, and typesand these five facets inform the core principles of integral psychotherapy (Forman, 2010;Marquis & Wilber, 2008;Wilber, 1995Wilber, , 2006. The quadrants are foundational among the five features and represent four basic perspectives that humans take on reality: subjective-individual, subjectivecollective, objective-individual, and objective-collective. Mapped together, these four perspectives provide a more complete and complementary view of any given phenomena. The four quadrants relate to the four other basic features of the integral approach-levels, lines, states, and types-each of which can be seen from the perspective of each quadrant (Forman, 2010;Marquis, 2007Marquis, , 2008Wilber, 1995Wilber, , 2006. It is beyond the scope of this article to describe each of these constructs other than to emphasize that an integral consideration fosters a more comprehensive assessment and understanding of clients (not only in terms of mental and physical health and well-being but also ecosystemically in terms of family, culture, community, social connections, resources, sociopolitical oppression, access to nature, and so forth). Fundamentally, the integral framework provides a conceptual means for therapists to work integratively and systemically across theoretical models and modalities, given their understanding of the evidence and of client needs and resources. It supports therapists and clients to think in terms of healing, growth, and development in prioritized areas and also assists therapists to consider the need for and to engage in client advocacy and in social and ecological justice.
Although much of the psychotherapeutic community remains unaware of this integrative, systemic, and holistic approach to working with clients and communities, integral metatheory is growing in influence (Baker, 2011;Combs, 2002;Esbjörn-Hargens, Reams, & Gunnlauson, 2010;Esbjörn-Hargens & Zimmerman, 2011;Forman, 2010;Ingersoll, 2010;Ingersoll & Zeitler, 2010;Schlitz, Amorok, & Micozzi, 2004). The benefits of using a metatheoretical approach to counseling have been identified and promoted by Ivey and colleagues (Ivey & Goncalves, 1988;Ivey & Rigazio-DiGilio, 1992). The current edition of Ivey and coauthors' (2012) theories of psychotherapy textbook offers Wilber's (e.g., 1995Wilber's (e.g., , 2000Wilber's (e.g., , 2006 integral metatheory as the lens through which to see each theory in an attempt to encourage students to consider a more comprehensive, developmental, and holistic approach. How widespread this integral, transtheoretical metatheory will become as a force in the wider psychotherapeutic community remains to be seen. This will depend, in part, on the ability of scholars and practitioners to foster its dynamic development in the face of sound criticism and to verify its relevance and utility to address the needs of individuals and groups in the complex global community. Nonetheless, the field has evolved toward inclusion and integration (of theories, praxis, and research), and there appears to be an increasing interest in holistic, ecosystemic approaches that aim to better meet the immediate and long-term needs of diverse individuals, families, and local to global communities. Finally, Walsh (2016) provided an extensive rationale for integrative, inclusive metatheories, emphasizing that they may better provide the tools needed "to address the great social, global, and ecological crises of our time" (p. xvii).

Conclusion
Ecological, multicultural, and systemic understandings of human nature, interrelationships, health, and pathology have changed dramatically over time, as have theories of personality and psychotherapy. This article offered a brief overview of the development of an evolutionary framework used to identify major movements in the field of psychotherapy for the last several decades. Reviewing the history of these forces provides information about how psychotherapy has been conceptualized from within, by a few, over time. It also sheds light on what theorists and mental health professionals may miss as they attempt to be comprehensive in their understanding of human nature and of what may be effective strategies to support individual and systemic change. This is especially true as psychology and psychotherapy become increasingly shaped by international voices, needs, and trends, as well as by advances in knowledge and technology. Attempting to be inclusive, holistic, and integrative, while knowing how to prioritize what may be most helpful for those in need, given the knowledge and resources available, seems to be essential keys as the field continues to evolve.

Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding
The author(s) received no financial support for the research, authorship, and/or publication of this article.