EN
Medical treatments are mostly based on nomothetic laws discovered by natural sciences. These, however, can hardly cope with the problems which arise from the individuality of the patients. Psychologists trained only in nomothetic perspectives are handicapped when they are to care individuals with health problems. Drawing on the principles of the science of complex systems a new theoretical framework emerges for the treatment of the individuality problems. Concepts like emergent properties and downward causation clearly demand other approaches to human functioning than the analytic one. Clinical data indicate that the sensitivity to stress cannot be exclusively explained by biological factors but it well correlates with the negative events in the so-called ethological dimension. In this vein psychologists should be expert at direct behavioural modification methods. Because of the arbitrary nature of verbal behaviour the functional contextualism as a philosophy for therapeutic change is invoked. The techniques of the Acceptance and Commitment Therapy developed by Steven Hayes proved to be a useful treatment approach for the problems derived from the paradox nature of human language. It is suggested that these new trends in behavioural sciences are worthy of consideration for those who are concerned with people's health.