One gains the impression from occasional remarks in the psychiatric literature that there is a feeling of dissatisfaction with the state of flux of the various concepts, serving as tools to help us understand our patients. This paper is submitted as an attempt to point out some of the reasons why psychiatric notions suffer from certain deficiencies. If, for the time being, we set aside the specific psychiatric problems confronting us in our daily work and muse over the structure of our psychological and psychiatric methods of explanation, we might come to the startling conclusion that these methods are quite inadequate. We medical people think in terms of the mechanistic natural sciences, particularly in terms of physics, chemistry and biochemistry. The importance of these auxiliary sciences to our art of healing the sick increases year after year and the outstanding results of chemotherapy, for instance, show how heavily our profession leans on chemistry. Beyond a doubt, the natural sciences are essential to the pursuit and the development of the practice of medicine, nevertheless, the question arises whether psychiatry should be based upon mechanistic methods in approaching our specific material, the human mind. Posed in this fashion, the question implies that psychiatric thinking is basically mechanistic in its general characteristics. I believe that one can prove this thesis on the premise that descriptions and explanations of human behavior are based upon neurological facts and theories. Since the purpose of neurology lies in a different direction than the goal of psychiatry, it was necessary to alter neurological concepts so that they would be more appropriate and fitting to psychic material, and this elaboration upon neurological principles when applied to mental phenomena leads to psychiatric conceptions with inherent deficiencies.