The law of relations stands in general reciprocal relationship to the law of resultants. Both of these laws apply to all compound unities of psychical phenomena, from the simplest ideational and complex affective processes up to the most complicated individual and general developments in psychical life. Thus the combination of a sum of tone elements into a single whole, by means of a specific ideational and affective value resulting from the combination itself, depends absolutely upon the qualitative and quantitative relations in which the tones stand to each other. This clearly arises from the natural dependence of resultants and relations upon each other, since each change of the latter modifies the constitution of the resultants in a corresponding manner. In the same way a spatial visual image is dependent on the relations of the qualitative and quantitative elements of the sensations of the retina and the strain sensations of the eye, and so on. A complex æsthetic feeling is a resultant of the simpler æsthetic feelings bound to the different parts of the perception, in so far as these latter again determine the product by means of their qualitative relations. And lastly all the processes of mental development are founded on the relations of their separate factors, by means of which they are combined into resultants. The interdependence of the laws of resultants and of relations shows us the importance of each of these principles. We cannot explain the psychical value of new creative compounds without considering the internal relations of their components, just as we cannot comprehend the peculiarity of these relations without continually taking into account their resulting influences.