Abstract
The scope of this introductory contribution is to present some general facts and ideas which could enhance our understanding of this enigmatic illness. By ‘mediating processes’ (or ‘mediators’) I mean mechanisms providing bridges between different aspects of knowledge of the schizophrenia-puzzle which, so far, have not been linked together in a satisfactory way: one of the central problems is the identification of mediators between psychosocial factors on the one hand, and biological factors on the other. If we do not succeed in building up conceptually valid bridges between these two aspects, which are testable for hypothesis-orientated research, a disastrous splitting of our understanding and treatment of schizophrenia into either biological or psychosocial reductionism is likely.