In the years between 1800 and 1914, the real beginning of the twentieth century, different etiological theories and models were developed about illnesses which we today know as schizophrenic disorders. Particularly in the German speaking world, in the first third of the nineteenth century many of these followed a religious metaphysical paradigm. Those who paved the way for modern psychiatry represented an etiological concept with varying emphasis on brain pathological, hereditary-degenerative or psycho-dynamic as well as sociogenic perspectives. It has become apparent that psychiatry was always in danger of giving way to reductionist approaches. Every reductionism emphasises merely partial truths. The systemic perspective teaches us that many points of view do not contradict each other but rather compliment each other.