Development of Brief Strategic Therapy: Historical Background-The Mental Research Institute of Palo Alto California

After the Second World War, in the 1950s, scientific conferences on cybernetics were organized in the United States, promoted by the Josiah Macy Foundation and organized by Warren McCulloch. They brought together a number of experts on the study of feedback, complexity, cybernetics, and their application to the various sciences. In this context, in 1958, Don Jackson founded the Mental Research Institute (MRI), an institution dedicated to research in the field of mental health. Don Jackson, Haley, and Weakland, began their pioneering work in the nascent family therapy studying the communicative patterns of families with schizophrenic members (^{Fisch & Schlanger, 2012}). Under the leadership of Don Jackson, the Mental Research Institute incorporated Paul Watzlawick into its team. Watzlawick's studies on change and the pragmatics of human communication were revolutionizing the field of therapy. An Austrian psychologist, with extensive knowledge and logical-philosophical training, Watzlawick had lived in El Salvador and joined the Palo Alto team in 1961 (^{Nardone, 2000}). Paul Watzlawick was one of the leading exponents of human communication theory. His field of research was focused on the pragmatic effects of communication. Research and interest in communication, up to that time, had focused on the syntactic and semantic aspects and not on the pragmatic aspects of communication (^{Watzlawick, 2007}). In 1961-together with Richard Fisch, John Weakland, and Jay Haley- Watzlawick was studying the methods of tranceless hypnosis and brief therapy. They were focused on the development of a shorter psychotherapy. They had been influenced by the celebrated psychologist and psychiatrist Milton Erickson. Erickson's influence was most notable in the development of the brief therapy model, from moving away from the traditions of psychopathology to the custom of assigning homework to patients (^{Fisch & Schlanger, 2012}). These techniques applied by Erickson had untraditional characteristics, often mistaken for "shamanism" but they hid a rigorous, consistent, and at the same time creative model (^{Nardone & Watzlawick, 2018}). The work of the Mental Research Institute (MRI) enabled the emergence of family systems therapy (^{Nardone, 2004}).

Creation of the Brief Therapy Center

When Don Jackson died in 1968, it was Richard Fisch who proposed the creation of the Brief Therapy Center (BTC). The team consisted of Watzlawick, Weakland, and Fisch. They brought fame to the Mental Research Institute through their research on human communication (^{Fisch & Schlanger, 2012}). The research group was oriented to search for new, more flexible, and brief forms of psychotherapeutic intervention, which could be adapted to different varieties of human problems. Their discoveries in the theory and pragmatics of communication contributed to the development of new psychotherapeutic techniques.

The approach to the works of the great hypnotherapist Milton Erickson allowed them to incorporate his vision and techniques, finding in their experience that the various problems could be solved, quickly, and definitively, in a brief therapy modality (^{Nardone & Portelli, 2017}).

The team also found that communication theory could be applied to various contexts beyond the family. A systemic model focused only on the family became rigid and limiting (^{Nardone & Balbi, 2018}).

In this way, the brief therapy center of the Mental Research Institute managed to develop a strict but at the same time flexible therapeutic model. Its work focused on reducing the duration of treatments, with a more functional and pragmatically focused directive therapist, achieving a first great revolution in the field of therapy (^{Ceberio & Watzlawick, 2006}).

The evolved model by Giorgio Nardone

Giorgio Nardone studied at the University of Siena in Italy, where he graduated with a thesis related to the philosophy of science; he admired Karl Popper and wanted to become a great epistemologist like him. There, as a student of the exceptional professor Mariano Bianca, he became involved in a research project that would later change the course of his life; he studied epistemology, focusing on the study of various models of psychotherapy. He concentrated on the epistemological aspects and their methodological soundness. By being involved in this research project, Nardone found that the therapy model of the Mental Research Institute (MRI), in Palo Alto California, covered the demanding methodological criteria they were studying (^{Nardone & Watzlawick, 2018}). Thus began this journey that would lead him to deepen his knowledge in the field of psychotherapy; he traveled with a scholarship to Palo Alto California, to the very heart of the Mental Research Institute. Having studied epistemology, Nardone traveled with the lens of the epistemological method of science; after his advanced stay at the Mental Research Institute, his life changed, turning from the epistemological aspects to the clinical aspects of psychotherapy. He was also fascinated by the results that he was able to observe and evidence in interaction with the great masters such as Paul Watzlawick. This awe and fascination led him to change career. He left the philosophy of science, and his mentor, Mariano Bianca, recommended him to the director of the psychology degree, and so began his studies in clinical psychology, while his links with the Mental Research Institute continued, concluding in 1985. Paul Watzlawick became his mentor, initiating Nardone's first research in Palo Alto.

In his clinical practice in Palo Alto, he saw patients with schizophrenia, psychosis, and relationship problems very frequently. However, upon his return to Italy, Nardone was surprised to find that, unlike the Mental Research Institute, most of the cases that came to him for consultation were rather patients with phobic and obsessive disorders. So, he put into practice what he had learned, using the original model of the Mental Research Institute, adapting it to the characteristics of the disorders encountered in his clinical practice in Italy. He broke with the traditional scheme, centered on family therapy and the need to see the patient with their family. It was a real violation of the dogmas of family therapy, more focused on theory than on the disorder and on the importance of the family rather than on the individual (^{Fiorenza & Nardone, 2004}). He saw patients individually, and thus a new therapy scheme emerged, to the astonishment and interest aroused in the great masters, such as Paul Watzlawick and John Weaklean.

After four years and more than 100 patients attended, the evolved brief therapy model was consolidated, and a first document was created in 1988, putting all that information and experience into six chapters of what would be Nardone's first book, "The art of change". This book was published in 1992 (^{Nardone & Watzlawick, 2012}). Paul Watzlawick, did him the honor of publishing it together. It became a best seller and the manifesto of brief strategic therapy. Subsequently, thanks to the success achieved, Nardone began to investigate other types of disorders such as eating disorders, bulimia, anorexia, among others. Thus, the research-action model with an experimental empirical basis expanded and so, in the year 2000, an important article called "brief strategy therapy" was published. It was a longitudinal study developed over 10 years and with 3,640 cases, with an average of 7 sessions (^{Nardone & Portelli, 2017}). Among the main results, they reported 95% efficacy in phobic and anxious disorders, which includes panic attacks and post-traumatic stress; 89% efficacy in obsessive and compulsive disorders; 91% efficacy in sexual dysfunctions; 83% efficacy in eating disorders; and 83% efficacy in depressive disorders (^{Nardone & Watzlawick, 2004}). The exclusive use of brief psychotherapy was reported in the protocol applied to all patients, which is a very important aspect to highlight. In this study, the model reported a high efficacy and efficiency without the use of drugs (^{Nardone & Portelli, 2017}). By 2004, with the systematization and incorporation of new techniques, new contexts were opened up, transcending the clinic to enter successfully into sports, coaching, education, management, and art. This was after more than 35 years of putting into practice the evolved model of therapy, using non-linear logics, and understanding the problem through its solution. The model has proven to have greater efficacy and efficiency than the traditional cognitive behavioral model, being more effective for eating disorders, obsessive compulsive disorders, and anxious disorders (^{Nardone & Balbi. 2018}). A comparative table between brief strategic therapy and cognitive behavioral therapy is presented in Table 1.

There are several studies showing the efficacy and efficiency of brief strategic psychotherapy. Among the most recent, we can mention a randomized controlled clinical trial conducted in Italy with inpatients and outpatients. The patients sought treatment for obesity and binge eating disorder. The results of the application of cognitive behavioral therapy and brief strategic therapy were compared. At six months follow-up, an overall improvement and a higher percentage of remission of binge eating disorder was observed in patients treated with brief strategic therapy compared to those treated with cognitive behavioral therapy (^{Castelnuovo et al., 2011}). In a study conducted with patients diagnosed with obsessive-compulsive disorder, the efficacy of brief strategic therapy was demonstrated for the treatment of these disorders (^{Pietrabissa et al., 2016}). In the same vein, in a subsequent randomized clinical trial conducted in 2018, whose objective was to determine the effectiveness of brief strategic therapy compared to cognitive behavioral therapy, the treatment of 60 Italian patients with binge eating disorder and obesity was evaluated. The study concludes that brief strategic therapy is clinically and statistically more effective than cognitive behavioral therapy for the treatment of binge eating disorders (^{Jackson et al., 2018}). In another longitudinal study conducted with a group of patients presenting with bulimia nervosa and binge eating disorder, the study demonstrated the efficacy of brief strategic therapy for the treatment of binge eating and bulimia nervosa symptoms (^{Pietrabissa et al., 2019}). In a recent study conducted in several countries applying brief strategic therapy to 1,150 cases with different psychopathological diagnoses, a complete resolution of symptoms was shown in 80% of cases with an average of 5.4 sessions and 5.3 months of treatment. These are data that must be taken into account due to the implications for patients, with a shorter treatment time and lower associated cost and without the use of drugs, demonstrating both the efficacy and efficiency of brief strategic therapy (^{Vitry et al., 2021}). In a post-pandemic context, treatments of short duration and proven efficacy are needed. Brief strategic therapy proves to be an alternative to be taken into account given its clinical and public health relevance.

Creation of the Centro di Terapia Strategica of Arezzo, Italy

Paul Watzlawick, the renowned psychologist and psychotherapist, member of the Mental Research Institute of Palo Alto California, founded the Center for Brief Strategic Therapy (CTS in Italian) in the city of Arezzo Italy, together with Giorgio Nardone, who is considered his intellectual successor. From the outset, the center was recognized for its high technical and academic level, which enabled the creation of a series of innovative techniques and the design of a series of specific treatment protocols for each disorder (^{Nardone, 2002}).

Professor Giorgio Nardone's work has been characterized by being innovative, which allowed him to develop treatment protocols based on the systematization of his experience, focused on the search for faster and faster solutions to various pathologies. His empirical-experimental clinical research, which combines therapeutic intervention and the formulation of strategies aligned to these pathologies, has allowed him to validate these strategies empirically, seeking efficiency and efficacy. He uses the empirical experimental method developed by Kurt Lewin, applied to the clinical field, which could be summarized as "understanding a problem through its solution" (^{Nardone & Portelli, 2017}).

Among the proposals that have emerged from the experience of the CTS of Arezzo and the clinical work of Professor Nardone is the strategic dialogue, which represents one of the cutting-edge techniques of the evolved model, combining a more evocative language, using paraphrasing and a strategically developed dialogue (^{Nardone & Salvini, 2011}). The rational logic of Aristotelian tradition is present in the way we humans solve and face problems and address our objectives and goals (^{Fiorenza & Nardone, 2004}). Contrary to this, the protocols have an organized and structured sequence of technical procedures which, following the Batesonian tradition, are able to adapt and self-correct as the intervention progresses, through the feedback received from the patient, which is flexible in its interaction with the symptom. Thus, the model becomes one that can be replicated, can be transmitted, and is predictable, maintaining efficacy and efficiency. It combines the scientific method with the sublime art, almost turned into magic, which is transmitted through the words and gestures of the therapist turned into a modern magician (^{Nardone, 2008}; ^{De la Cruz, 2013}). The therapist follows an established protocol, but adapts the therapeutic method to each patient, to their worldview, to their way of relating, to the specific characteristics of each pathology. The flexibility of the model allows the therapist to adapt to each patient. Since it allows this space to be able to create, use their creativity, and innovate, in that sense it is artistic (^{Zaldivar, 1995}; ^{Riveros, 2013}). There is art in the way a prescription is made, in using a metaphor, in designing a task, in using the body and prosody. The technical procedure of each protocol is complemented by creative and artistic flexibility in the execution (^{Nardone, 2013}). Brief psychotherapy thus becomes an artistic space of creation and not just a rigid procedure to be complied with.

Epistemology and Foundations of Brief Strategic Therapy

From Aristotle to Newton via Descartes, Aristotelian logic dominated the Western world, proclaiming the supremacy of the so-called "goddess of reason" and laying the foundations of traditional linear logic, serving to understand the world, to understand our relationships with ourselves, with each other, and with the world. The advance of physics oriented to the study of the atom facilitated the emergence of new theoretical constructions. The discoveries arising from quantum physics, in contrast to the Newtonian model of physics, enabled the subsequent emergence of new ideas in the rest of the sciences. General systems theory and cybernetics help to strengthen the model and provide the epistemological framework that drives the theoretical development of the emerging systemic family therapy. The contributions of Maruyama, Bertalannfy, Wienner, Shannon, Von Foerster, Prigogine, and many others are vital for the emergence of what would later be known as the first cybernetics or the cybernetics of observing systems. This is a position in which the observer studies the system and remains external to it (^{Watzlawick, 2007}). In the first cybernetics the therapist intervenes to solve the problems brought to them by the families or patients, a reality external to the therapist on which it is necessary to intervene in order to modify it and provide a solution. Later, with the emergence of the second cybernetics, constructivism, and the inclusion of the observer in what is being observed, the questioning of objectivity and certainty gained strength. The deepest foundations of Newtonian science were shaken and the basis of our perception of reality questioned. Now, the existence of a single reality is questioned (^{Nardone, 2003}). The observer is included in what is being observed, an observer who participates through observation in the definition and construction of what they are observing, making it impossible for objective observations to exist, since it is impossible for them to observe without including themselves in what they are observing. In the second cybernetics, the therapist intervenes on meanings rather than on behaviors (^{Nardone 2000}; ^{De la Cruz, 2008}). These are the epistemological bases of brief strategic therapy centered on constructivism, the inclusion of the observer, the questioning of an objective reality, and second-order cybernetics.

Construction of solutions

From an Aristotelian linear causality perspective, it is assumed that to solve a problem we must discover the causes and find the origin of the problem and by doing so we can find the solution. However, applying this strategy to complex human problems is ineffective (^{Fiorenza & Nardone, 2004}). Human interactions are not based on traditional Aristotelian logic, but on logical ambivalence, belief, paradox, and contradiction. It is therefore required to break the rigid limits imposed by formal logic to assume a strategic logic based on a model of action planning in which the objectives and goals to be attained lead to the solution of the problem (^{Nardone, 2010}; ^{Nardone & Bartoli, 2019}). It is posited that human problems in their various forms are the result of the interactions that human beings themselves establish, such that each person constructs his or her particular reality, thus building the prisons and the reality that he or she will then endure (^{Nardone, 2008}). The problem is fed back in the interaction between the subject and their reality, through a complex series of perceptual and reactive feedback (^{Watzlawick, 2007}). Brief strategic therapy does not focus on the past, it puts the focus on the present and from there it is oriented to the future, building a new reality and a different future. It assumes that by modifying the attempted solution, the symptomatic sequence is broken, making the emergence of therapeutic change possible. Together with the client, the therapist establishes therapeutic goals to be achieved, realistic goals that can be reached by seeking to build self-efficacy (^{Nardone, 2008}; ^{Nardone, 2010}; ^{Nardone & Brook, 2010}).

Brief strategic therapy identifies everything that the patients do to try to solve the problem and that paradoxically generates it. It is thus proposed that there is another way of intervening, based on the assumption that to solve human problems it is not necessary to study the causes or seek the origin of the problem, but rather to focus on the functioning of the problem (^{Watzlawick, 2008}). In this way, the focus of intervention is changed from seeking the origin of the problems, under a linear causality, to finding solutions, under a circular causality.

In this way we understand the pathology based on its solution; if the therapeutic model allows a rapid and effective cure of the disorder, it indicates that its structure fits the pathology described. The implementation with a large sample of people suffering from the same pathology sheds light on the fact that the solution explains the problem, that we are able to understand the problem based on its solution (^{Nardone, 2008}). Nardone, through his model, teaches us that, in order to provide a solution to the various psychopathological disorders, we must direct our focus of observation to the practical aspects of the therapeutic techniques that are most effective and efficient, and not remain only with the "objective" description of the characteristics of the disorder (^{Nardone, 2010}). This change of focus from the description of the clinical characteristics of the disorder to the practice of the solution, looking for the most suitable therapeutic treatment for each disorder, leads us to understand the problem based on its solution. The aim is to adjust the therapeutic practice to the clinical symptom, combining research and action, from systematizing and incorporating other techniques used both at the Mental Research Institute and by other masters of psychotherapy, as well as new techniques, true gems that are the product of inventiveness and experience. The evolution of pathologies, the cultural aspects, and the digital context enrich the clinical practice and allow the synergic emergence of a robust model that over the years is one of the most efficient and effective for a multiplicity of pathologies (^{Nardone, 2020}).

As can be seen in Figure 1, the strategic dialogue process simulates a narrowing funnel (^{Nardone & Seleckman, 2013}). It guides the therapist and patient towards the understanding of the problem. Together they make this joint discovery through the strategic questions and paraphrases. The cooperation between therapist and patient becomes evident. In this discovery, the patient's perception changes, which facilitates their cooperation. The structure of a strategic dialogue is presented below.

Note. Adapted from Hartarse, vomitar, torturarse [Gorging, throwing up, and torturing yourself] (p.58), by ^{Nardone and Seleckman, 2013}, Herder.

Figure 1. Outline of the Strategic Dialogue. 

T: What is the reason for your visit?

P: I haven't been able to control my anger for some time. It troubles me a lot.

T: And this lack of control, does it happen a few times a week or every day?

P: A few times a week, I get filled with anger and in desperation... I eat up all the anger until I can't stand it and explode by punching the wall with my fists.

T: Ok, I understand, so do you explode by hitting the wall and do you do it only with your fists or also with another part of your body?

P: I usually punch the wall when I can't hold my anger. Sometimes I also hit my head against the wall. A year ago, I got a head injury, and it bled, so I had to go to the emergency room. Usually, it's just with my fists.

The therapist then makes a paraphrase, seeking a first agreement on the definition of the problem.

T: If I have understood you correctly, correct me if I am wrong, you have come here because you have a problem that has been troubling you for some time and that is that you cannot control your anger. Do you sometimes punch the wall because you cannot hold your anger, was there an occasion when you hit with your head, and you had to be treated in the emergency room, is that right?

P: Yes, that's right. The more anger I have, the more I hurt myself. A series of thoughts come to me that trouble me a lot.

T: I understand. Are these thoughts that come to your mind always the same or do they change?

P: It's always the same ones. They remind me how idiotic and stupid I am... I keep arguing with my mother... I complain to her and my father (deceased) for everything that happens to me... At 32 years old, I haven't accomplished anything. I just lost my job; a few months ago my partner left me; I haven't finished college; my life is a complete disaster (crying)... I'm an idiot...a failure… My parents didn't support me, they just screwed up my life... All that impotence fills me with rage and anger.

The therapist then uses a paraphrase with the aim of making the patient feel their proximity and emotional contact. The therapist also transmits a restructuring of the disorder.

T: I understand... You feel great emotional pain that is relieved by physical pain... It seems that you hit the walls in an attempt to anesthetize your deep pain because you think your life is a total disaster. It is pain that you try to run away from, a palpable pain from which there is no miracle medicine that can cure it.

P: Yes, I try to run away from my thoughts, from my memories, from my life. I run away from knowing I'm a failure… I'm seeking refuge, and hitting effectively relieves me of this pain, although it is only temporary because then it comes back stronger.

The agreement is reinforced, and a restructuring paraphrase is used.

T: Indeed, hitting works well for you in the moment when you do it. The physical pain you feel when you hit things has the effect of distracting you and forgetting about your great emotional pain, but when the effect wears off you discover that the emotional pain is still there waiting for you, ready to cause you deeper and more painful wounds.

P: Yes, that's how it works. It calms me down, but then it comes back even stronger and hurts me even more.

Now use a question with an illusion of alternative answers.

T: OK, so all this is what you do and have been doing to relieve your pain. Does it really work or is it something that only gives you momentary relief that then generates deeper pain?

P: I realize that these outbursts of anger that lead me to hit the wall with my fists only give me momentary relief and in the end nothing has changed. It is still temporary relief, and my emotional pain is still present.

Therapist uses an evocative image.

T: Look, when a person has a deep wound and keeps scratching it without letting it heal, the only thing he achieves is to infect it more and more... In order to heal a wound, you must first clean and disinfect it, and then let it scab over, allowing it to finish healing naturally.

P: Yes, you are quite right. The only thing I have achieved is to further infect my wounds.

Ask a question with an illusion of alternatives.

T: So far, and according to what we have been able to analyze, if this whole situation were to continue, can the pain you feel be alleviated or will it be maintained and fed more as time goes by?

P: I definitely realize that if I don't do something different, I will continue to have the same results, and nothing will have changed.

In the sequence of the strategic dialogue, the therapist is creating the need for change. This facilitates the reception of the prescription as a joint discovery, encouraging the patient's cooperation in the therapeutic process.

T: As we saw and analyzed together, we can begin to disinfect and finish healing the wound. To do this, let me suggest that you get some sheets of paper and every night before going to bed, write a letter describing in great detail everything that has made your life a complete disaster. Write about everything you have told me, write everything that comes to your mind in relation to this. When you have finished, put the letter in an envelope and bring it to our next session. Remembering all this will be painful, but it is very important for healing. Regarding hitting the wall, when you feel the desire and the urge to hit the wall, go to the bathroom, stand in front of the mirror, look at yourself in the mirror, and ask yourself, “Do I want to heal the wound, or do I want to continue to maintain it and infect it more?” Then decide whether you want to do it or not.

The indications were accepted by the patient. In the following sessions the patient showed a remarkable improvement. Both the prescription and the indication that they should look at themself in the mirror reinforces the aversion created in the process of the strategic dialogue. It also alters the recursive pattern of the symptomatic behavior. After the application of the strategic dialogue, the patient perceives the procedure as a possible way out and is more open to accept the prescription. As can be seen, the model can maintain the structure of the dialogue and its sequence, thus maintaining the methodological rigorousness and procedure. However, it is flexible since it can be adapted and modified to each individual patient. The contents of the dialogue, the relationship between therapist and patient, as well as the techniques are all adapted to each specific patient and disorder.

Strategic logic and change

In brief strategic therapy we start from the assumption that the strategic logic adapts to its object of study, from this perspective it is always the solution that must be adapted to the problem and not the other way around, thus aiming to avoid a universal and objective mode of intervention. We abandon the thesis that there is a scientifically true knowledge, to seek a more functional knowledge (^{Von Foerster, 1991}; ^{Von Glasersfeld, 2014}).

The Cartesian idea that change is the effect of a gradual and slow process of awareness or insight on the part of the patient is still valid. After this process, he or she chooses to behave differently by modifying his or her actions and cognitions. The model of brief strategic therapy considers change as a constant, a continuous process that is sometimes obstructed due to the disorder, but thanks to the therapeutic intervention we can unblock it to allow its natural evolution. It considers that human beings construct our representations of reality, representing ourselves, others, and the world, forming a perceptual-reactive system that maintains its homeostasis and resists change (^{Fiorenza & Nardone, 2004}). In a traditional, more positivist approach, it is conceived that we can have a real interpretation of an objective world. The therapist has privileged access to an absolute truth and, based on this real and objective knowledge, he or she is able to intervene and heal the patient. On the contrary, brief strategic therapy, successor of the sophists and the constructivist tradition, considers that we cannot grasp the world in a real and objective way (^{Segal, 1994}; ^{Nardone & Portelli, 2017}; ^{De la Cruz Gil, 2021a}).

What we call reality is rather the product of the perspective with which we perceive phenomena, the instruments of knowledge we use, and the language with which we construct this reality and communicate it (^{Nardone & Portelli, 2017}).

It is posited that any phenomenon that the psychotherapist, as an observer, tries to understand about their patient, cannot exist independently of the therapist's own cognitive and perceptual processes, and cannot exist independently of his or her own theoretical models, thus rejecting any theory that aims to objectively describe reality or establishes a priori strategies and interventions to treat it (^{Nardone & Watzlawick, 2018}; ^{Nardone & Portelli, 2017}).

All knowledge of our client is only an approximation to reality. It is the product of the particular perceptual and cognitive processes with which the therapist constructs reality. The strategic approach therefore represents the passage from a positivist and deterministic knowledge to a functional knowledge. This allows us to manage reality functionally. It focuses on pragmatic aspects, centered on the process of change and on the observation of the persistence of the problem. The aim is to understand how things work and is concerned with how to make them work better, to provide wellbeing to the patient in a more efficient and effective way (^{Nardone, 2010}).

Functional diagnostics and perceptual-reactive system

This model represents the constructivist epistemology of Gregory Bateson. It does not use explanatory theories of the symptom and disorders. It is possible to understand the problem based on the solution, which implies being able to change a reality by intervening in it (^{Nardone & Salvini, 2011}; ^{Nardone, 2013}). Science seeks to understand the problems first through a normative theory, based on the description of human nature and all its pathological deviations (^{Nardone, 2013}). From the moment a person is attributed a psychiatric diagnosis, any behavior he/she performs will be a confirmation of the diagnosis. Assuming a constructivist position implies renouncing rigid and deterministic theories, classifications, and models (^{Nardone, 2008}). This is why in brief strategic therapy, when defining a problem, a functional diagnosis or intervention diagnosis is used instead of a descriptive diagnosis. In the traditional diagnosis, the disorder is described as a photograph, without suggestions as to how the problem works or how it can be solved (^{Nardone, 2002}). The evolved model goes beyond the descriptive nosographic classification used in psychiatry in the DSM, adopting the categorization model in which the "perceptual-reactive" system construct replaces the DSM category (^{Nardone, 2004}).

The perceptual-reactive system involves the redundant modalities used by the person towards reality, in his or her relationship with him- or herself, with others, and with the world (^{Watzlawick, 2012}). The functional description used by the evolved model involves a type of cybernetic-constructivist description centered on the persistence modality of the problem, therefore it is possible to understand a reality by intervening on it. In order to solve a problem, it is more interesting to understand how it is maintained and how it works. It ceases to make sense how the problem was generated and what its causes were. The only epistemological variable that we can control is the therapist's own strategy, i.e., his or her own tentative solution, which, when it works, allows the therapist to understand how the problem persisted and was maintained (^{Nardone, 2004}).

Brief strategic psychotherapy seeks to increase functional awareness, that involves the transition from understanding as a representation of objective reality to understanding as a more adapted representation of reality (^{Von Glasersfeld, 2014}). In this way these modern sophists rely on a strategic logic focused on objectives, adapting their intervention to the specific characteristics of each problem. A change in causality is evidenced, moving from a linear causality to a circular causality, interested in understanding how we can break the sequences and patterns of the problem (^{Nardone, 2008}; ^{De la Cruz Gil, 2021b}).

Conclusions

Brief strategic therapy is a non-normative model, conceiving human problems as the result of interactions between the person and his or her reality; moving from the study of why to the study of how the problem works. It seeks to intervene by modifying a reality based on the intervention for that reality. It is based on the assumption that to solve human problems it is not necessary to study the causes or look for the origin of the problem, but to focus on the functioning of the problem. In this way, the problem is understood based on its solution, the solution being the one that adapts to the problem.

Brief strategic therapy uses a functional diagnosis or intervention diagnosis, rather than a descriptive diagnosis. It goes beyond the descriptive nosographic classification used in psychiatry in the DSM model, replacing it with the construct of perceptual-reactive system.

It leaves behind any dogmatic theory, which is why it is far removed from the systemic branch of family therapy. It does not claim to prove the validity of a theory. It avoids focusing on previous hypotheses. It seeks to achieve the objective set with the client, focusing on the present, by developing actions that seek to achieve the therapeutic objectives.

The great theoretical development in the strategic field has allowed it to transcend the clinical field, leading it to constitute a true school of thought, now encompassing various fields such as management, coaching, sports performance, organizations, leadership, and education, among others.

Brief strategic therapy has demonstrated efficacy and efficiency in several controlled clinical trials. In its therapeutic protocols it does not use or incorporate the use of drugs. The reduced number of sessions and its broad efficacy for various emotional disorders allow it to have clinical relevance.

In the current post-pandemic context, it is necessary to have effective and efficient interventions, in this sense we consider that brief strategic therapy can contribute to the development of mental health. We suggest evaluating its incorporation into healthcare and public health programs.