Gestalt therapy falls within the category of humanistic psychotherapies. It was Friederich Perls, a German Jewish psychoanalist, whose intuition gave rise to this form of therapy: he had emigrated in the Forties, because of his race, first to South Africa and subsequently to the United States, where his insight was further developed by a group of American intellectuals with a deep knowledge of psychoanalysis. Of these the most outstanding were Paul Goodman, Laura Polsner (Perls's wife), Isadore From, Paul Weisz, Lotte Weisz, Elliot Shapiro, Alison Montague and Sylvester Eastman. The birth of Gestalt therapy was the expression of the creative synthesis of various philosophical and psychological cultural tendencies which, in the post-War period, fully revealed new cultural paradigms. Besides Gestalt psychology, of which Perls had had direct experience when he was working as Goldstein's assistant, and of course psychoanalysis, other contributions to the formulation of his thinking came from his experiences of individual analysis with Wihelm Reich (Salonia-Spagnuolo Lobb, 1988) and with Karen Horney (Salonia 1990; Cavaleri 1990; 1991), Otto Rank's theory on the crucial importance of the ìcounter-willî for the differentiated and creative growth of the human individual (Rank, 1932; Müller, 1991; Davidove, 1993), then Holism in its theoretical formulation by Jean Smuts (Robine, 1993), Existentialism and Phenomenology, in which Perls was trained by Isadore From (Rosenfeld, 1987), and finally Oriental philosophies, especially Zen.

Friedrich Perls had been Kurt Goldstein's laboratory assistant in Germany, and was thus intimately involved in the enthusiastic studies of the perception of Gestalt therapy. His dissatisfaction with the Freudian theory of the Ego led him to realize that introjection completes its fundamental evolutionary task much earlier than Freud had theorized. For Perls, teeth development (the dental phase) is the physiological proof of all this. If the newborn child's sucking its mother's milk creates or sustains the human capacity - at a physiological as well as a psychological level - to introject, teeth development must likewise create (or maintain) a physiological or psychological capacity on the part of the child, namely the capacity to deconstruct both food and reality, to attack them in order to be able to assimilate them, if they are nourishing, or reject them if they are harmful or non-nourishing. The ability to chew and bite which teeth development gives to the organism puts absolute emphasis on aggressiveness at a moment of evolution significantly earlier than Freud had theorized. Moreover, Perls saw aggressiveness itself in the positive terms of the survival and physical and existential growth of the organism: the drive to self-fulfillment is thus spontaneously attained. Goldstein's positive perspective of the impulse to self-fulfillment was a fundamental influence on Perls's thinking, which was offered as a way of overcoming the dualism present in Freudian metapsychology between the individual's impulses and the need for social organization. Indeed, since the individual is the subject who deconstructs and reconstructs, this means that s/he has a real possibility of living fully in her/his own world.

The three key words in the title of Perls's first book, written originally in 1942, even before the foundation of Gestalt therapy - his The Ego, Hunger and Aggression (Perls, 1969) - express in condensed form his criticism of the Freudian theory of human nature: namely, that Freud had not given due emphasis to the ability of the Ego to satisfy its own needs (hunger) by means of a self-affirming activity (aggression), which enables the Ego to assimilate or reject the environment according to whether it is seen as nourishing or harmful. Thus the Ego, hunger and aggression become the pillars of this new psychotherapeutic model, whose bases are contained in Gestalt Therapy: Excitement and Growth in the Human Personality, by F. Perls, R. Hefferline and P. Goodman (1951). Basically they maintain that every experience must come about at the contact boundary between a human animal organism (it was in these organicist terms that the founders of Gestalt therapy expressed themselves) and her/his environment. It is precisely what happens at this boundary that is open to observation and to a possible therapeutic intervention. The contact boundary is the place where the Seif unfolds - the Self being that function of the human organism which expresses its ability to make contact with its environment and to withdraw from that environment. As a function, the Self may be divided into three aspects: the Id function of the Self (Perls et al., 1951, 433), the Personality function of the Self (what the Self has become by assimilating into the organism the results of previous contacts) and the Ego function of the Self (the progressive identifying with, and alienating from, parts of the self and the environment, thanks to the use of the will; Perls et al., 1951, 432ff.). The process of contact between the human organism and its environment, explained in Gestalt therapy on the basis of the dynamic concept of function - without reference to specific instances - allows the invidual to learn to orient her/himself in the world, and to act on it for the self-preserving purpose of assimilating what is new - what is different from the self - and growing.

Thus the contact boundary is the place where creativity (which expresses the uniqueness of the invidual) can be combined with adjustment (which expresses that reciprocity which is necessary to social living). The way the invidual does or does not make contact with her/his environment describes her/his psychic functionality. And the concept of maturity in Gestalt therapy can be traced to creative adjustment, understood as the goal of the healthy development of the individual. It does not answer to a univocal model of health (From, 1985), but permits individual modulation on parameters of self-fulfillment and willing acceptance of the novelty offered by the environment or by the other. The needs of the invidual and of the community are integrated without sacrificing any one of them 'a priori'(Perls et al., 1951, 456ff.). Hence in Gestalt therapy a person's growth towards autonomy coincides with her/his capacity to decide in favor of contact with the other, with the Thou (Rosenfeld, 1986).

On the clinical level, certain substantial differences of psychotherapeutic practice follow from Perls's ideas: we may think, for instance, of the positive redefinition of the patient's aggression, of the value given to the capacity to concentrate (which Perls substituted for free association) as recovery of spontaneity of the organism, and of the brillant replacement of the cause-and-effect concept with the concept of function (From, 1985).

Later developments of the theory and practice of Gestalt therapy have been characterized by a variety of schools, which unhappily have not always given due emphasis to the theory of experience of contact-withdrawal, which is the basic novelty of this approach in the context of humanistic psychotherapies (Wysong, 1994). These schools fall into three trends: the three souls of Gestalt therapy (Salonia, 1991). The New York school, which has remained faithful to the ideas and also to the cultural climate of the group of founders, has developed them in psychotherapeutic theory and practice. The so-called ìvisceralî movement, which developed along the Pacific coast of the United States, after the miraculous demonstrations (i.e. demonstrations unsupported by theoretical explanations) by Perls with groups of patients intrigued by the use of dramatization in the therapeutic setting, sees consciousness/awareness as the therapeutic tool and places value on subjectivity, the body and the emotions in the growth of the individual. Lastly, the Cleveland school represents a more eclectic orientation, which focuses on the creation of a language which it shares with other therapeutic approaches, and on the application of Gestalt therapy to various fields of social interaction, such as the family, groups, organizational consulting, etc.

The socio-pedagogical perspectives which Gestalt therapy can offer to those concerned at various levels with change, healing and education may be reduced to three fundamental aspects. Above of all, space must be given in the process of growth and training to the aggressive strength, the independent expression of the no of the patient and user or trainee, such that s/he may be given that humanly significant experience of exercising her/his will, without this being in conflict with the importance of a regulative restraint for the learner. Secondly, a Gestalt perspective (which might also be called holistic), according to which the individual and the social group are no longer seen as separate entities but as parts of a single unity in reciprocal interaction, so that the tension which there may be between them is not to be regarded as the expression of an indissoluble conflict but as the necessary movement within a field which tends towards integration and growth. Thirdly, the relational perspective as a key to reading human behavior, so that every experience finds its meaning - also in terms of intentionality - in the relationship within which it is inserted (Salonia, 1992). This restores concreteness to the exigencies of the individual and of social living: every conflict is to be faced in the here and now of the situation, because it is only in the details of a context that we can find real solutions. Gestalt therapy entrusts the regulation of need to the relationship itself, because it is in full recognition of the self and the other that the needs of the interacting partners find healthy expression and creative resolution.

This model of psychotherapy might be criticized for the lack of uniformity of its theoretical and methodolgical body, which in the last analysis actually derives from an intrinsic aspect of its epistemological foundations: its emphasis on the importance of the human capacity to deconstruct reality. Understanding the creative, meaningful contribution which the aggressive strength of the organism gives to human relations has taken the place of a theoretical climate which at times seemed to value rebellion as an end in itself, which has undermined to a significant degree adherence to those paradigms whose originality characterized the foundations of the approach itself. If on the one hand it gave Gestalt therapists the richness and flexibility which arise from a constant confrontation with differences, on the other hand it did not guarantee the clear, and clearly expressed, differentiation of this theory compared with other theories. The result has been to favor the development of various currents within Gestalt therapy, and these currents are often largely unconnected.