Psychical facts are occurrences, not objects; they take place, like all occurrences, in time and are never the same at a given point in time as they were during the preceding moment. In this sense volitions are typical for all psychical porcesses. Voluntaristic psychology does not by any means assert that volition is the only real form of psychosis, but merely that, with its closely related feelings and emotions, it is just as essential a component of psychological experience as sensations and ideas. It holds, further, that all other psychical processes are to be thought of after the analogy of volitions, they too being a series of continuous changes in time, not a sum of permanent objects, as intellectualism generally assumes in consequence of its erroneous attribution to ideas of those properties which we attribute to external objects. The recognition of the immediate reality of psychological experience excludes the possibility of the attempt to derive the particular components of psychical phenomena from any others specifically different. The analogous attempts of metaphysical psychology to reduce all psychological experience to the heterogeneous, imaginary processes of a hypothetical substratum are, for the same reason, inconsistent with the real problem of psychology. While it concerns itself, however, with immediate experience, psychology assumes from the first that all psychical contents contain objective as well a subjective factors. These are to be distinguished only through deliberate abstraction, and can never appear as really separate processes. In fact, immediate experience shows that there are no ideas which do not arouse in us feelings and impulses of different intensities, and, on the other hand, that a feeling or volition is impossible which does not refer to some ideated object.
10. The governing principles of the psychological position maintained in the following chapters may be summed up in three general statements.
1) Inner, or psychological experience is not a special sphere of experience apart from others, but is immediate experience in its totality.
2) This immediate experience is not made up of unchanging contents but of an interconnection of processes; not of objects, but of occurrences, of universal human experiences and their relations in accordance with certain laws.
3) Each of these processes contains an objective content and a subjective process, thus including the general conditions both of all knowledge and of all practical human activity.
Corresponding to these three general principles, we have a threefold relation of psychology to the other sciences.
1) As the science of immediate experience, it is supplementary to the natural sciences, which, in consequence of their abstraction from the subject, have to do only with the objective, mediate contents of experience. Any particular fact can, strictly speaking, be understood in its full significance only after it has been subjected to the analyses of both natural science and psychology. In this sense, then, physics and physiology are auxiliary to psychology, and the latter is, in turn, supplementary to the natural sciences.
2) As the science of the universal forms of immediate human experience and their combination in accordance with certain laws, it is the foundation of the mental sciences . The subject-matter of these sciences is in all cases of the activities proceeding from immediate human experiences, and their effects. Since psychology has for its problem the investigation of the forms and laws of these activities, it is at once the most, general mental science, and the foundation for all the others, such as philology, history, political economy, jurisprudence, etc.
3) Since psychology pays equal attention to both the subjective and objective conditions which underlie not only theoretical knowledge, but practical activity as well, and since it seeks to determine their interrelation, it is the empirical discipline whose results are most immediately useful in the invention of the general problems of the theory of knowledge, and ethics, the two foundations of philosophy . Thus, psychology is, in relation to the natural sciences, the supplementary, in relation to the mental sciences the fundamental, and in relation to philosophy it is the propaedeutic empirical science.
10a. The view that it is not a difference in the objects of experience, but in the way of treating experience, that distinguishes psychology from natural science has come to be recognized more and more in modern psychology.
Still a clear comprehension of the essential charactor of this position in regard to the scientific problems of psychology, is prevented by the persistence of older tendencies derived from metaphysics and natural philosophy.