Identity of medicine is determined by its constitutional and essential characteristics that identify it with itself and deliminate medicine from other fields of science. Its basic principle is a new philosophical view on the health and disease and their mutual relationship. To the four traditional models of health the fifth one is added - the continual bio-psycho-social concept: The complex health-disease is a dynamic entity formed by a continuous array of mutually interconnected stays of variously large and measurable health capacity, sensitively responding to stimuli of the social environment. Opinions on the disease causes are expressed in the bio-ecologic model, based on the view of multicausality and multilevel effects of various different factors at all structural levels, among which the principal role has the socio-economic macrosphere.

        Key words: identity, positivism, phenomenology, paradigm, socio-ecological model of disease, health-disease, multilevel aetiology, health determinants, multifactorial eco-epidemiology.