During that period von Bertalanffy as a young scholar was not only interested in biology and philosophy of science. He was also interested in history… - Thaddeus E. Weckowicz

When one turns to psychological models of mental illness, one finds that the psychodynamic model of human mind and of mental disease is also of considerable antiquity. Thus, Empedocles of Agrigentum (490-430 B.C.) from whom Hippocrates took the theory of four elements, stressed the importance of emotions of love and hate as the controlling agents of human behavior and of physiological functions.

The preceding chapters described various models of mental illness. Seven major varieties of models have been described. Seven major varieties of models have been described. Three are scientific: medical, psychological, and sociocultural. Four are philosophical-moral: hermeneutic-linguistic, phenomenological- existential, humanistic, and moral-legal. Most of these major varieties can be divided into more circumscribed models giving rise to a total number of fifteen. In turn, some of these may be further divided into submodels. Thus, there are three psychodynamic, three behaviouristic, two cognitive, two macro- and two microsocial, two linguistic-symbolic, # two phenomenological, two humanistic, two hypersanity, and three moral-legal submodels. The detailed classification of the models of mental illness is presented in Tabel II.

Depersonalization is a concept difficult to delineate. It can be regarded as a symptom or as a loosely associated group of symptoms that occurs in psychiatric patients. It can be induced experimentally and also occurs spontaneously in normal subjects. A major obstacle to clearer definition of this concept lies in the fact that it refers to exceedingly private events in the individual's experience. These prove very difficult to describe by a language geared to the description of public (consensually validated) events or private events, such as pain, that occur usually in clearly defined social settings. When it comes to describing and conveying something as ineffable as depersonalization or derealization, the subject resorts to metaphors, "as if" expressions, and figures of speech. The result is semantic confusion. Different authors mean different things when they use the term depersonalization. The concept of depersonalization merges by imperceptible degrees with the concept derealization, the concept of altered body image and self, deja vu, jamais vu, altered time and space perception and so on - the whole gamut of phenomenological description of the experiences of mental patients. Therefore, it is rather difficult to evaluate and to review objectively the psychiatric literature on the phenomena of depersonalization.