["Border-line states": psychodynamic and existential approach, apropos of 8 case reports].

This study attempts to determine the specific characteristics of this psychopathological concept, and demonstrate its operational interest. The traditional classification is clearly insufficient, and the clinical findings require metapsychological and existential references. The comprehensive approach to these morbid forms with polymorphic outlines, and variable symptoms, implies a deeper approach to the psychodynamic and structural planes. The experience of these subjects is characterised by sadness and lack of pleasure in life; they oscillate between a feeling of solitude, to which may be attached an anguish of separation and a flight from others when their relationship does not correspond to their special requirements and their modes of exchange with, in addition, an intrusion anxiety. Two references, one to Feeling alone by M. Klein and the other The ability to remain alone by D.W. Winnicott shed light on the psychogenetic basis and on the prevalence of phenomena of idealisation. The coexistence of sectors of mental function and defence mechanisms of different registers intervening together or alternately explain the "stability in instability". The existential continuum bears the traces of sudden ruptures. This paper includes the presentation of 8 cases.