15. From the aggregate ideas thus resulting from apperceptive synthesis there arise two forms of apperceptive activity in the opposite direction of analysis. The one is known in popular parlance as activity of the imagination, the second as activity of the understanding. The two are by no means different, as might be surmised from these names, but closely related and almost always connected with each other. Their fundamental determining motives are what distinguish them first of all and condition all their secondary differences as well as the reaction that they exercise on the synthetic function.
In the case of the activity of "imagination" the motive is the reproduction of real experiences or of those analogous to reality. This is the earlier form of apperceptive analysis and rises directly from associations. It begins with a more or less comprehensive aggregate idea made up of a variety of ideational and affective elements and embracing the general content of a complex experience in which the single components are only indefinitely distinguished. The aggregate idea is then divided in a series of successive acts into a number of more definite, connected compounds partly spacial, partly temporal in character. The primary voluntary synthesis is thus followed by analytic acts which may in turn give rise to the motives for a new synthesis and thus to a repetition of the whole process with a partially modified or more limited aggregate idea.
The activity of imagination shows two stages of development. The first is more passive and arises directly from the ordinary memory-function. It appears continually in the train of thought, especially in the form of an anticipation of the future, and plays an important part in psychical development as an antecedent of volitions. It may, however, in an analogous way, appear as a representation in thought of imaginary situations or of successions of external phenomena.
The second, or active, stage of development is under the influence of a fixed idea [p. 263] of some end, and therefore presupposes a high degree of voluntary control over the images of imagination, and a strong interference, partly inhibitory, partly selective, with the memory-images that tend to push themselves into consciousness without voluntary action.
Even the first synthesis of the aggregate idea is more systematic. An aggregate idea, when once formed, is held more firmly and subjected to a, more complete analysis into its parts. Very often these parts themselves are subordinate aggregate ideas to which the same process of analysis is again applied.
In this way the principle of organic division according to the end in view governs all the products and processes of active imagination. The productions of art show this most clearly. Still, there are, in the ordinary play of imagination, the most various intermediate stages between passive imagination, or that which arises directly from memory, and active imagination, or that which is directed by fixed ends.
16. In contrast with this reproduction of real experiences or of such as may be thought of as real, which constitutes the content of the apperceptive functions that we include under the concept "imagination", the fundamental motive of the "understanding " is the perception of agreements and differences and other derived logical relations between consent of experience. Understanding also starts with aggregate ideas in which a number of experiences that are real or may he ideated as real, are voluntarily set in relation to one another and combined to a unitary whole. The analysis that takes place in this case, however, is turned by its fundamental motive in a different direction.
It consists not merely in a clearer grasp of the single components of the aggregate idea, but in the establishment of the manifold relations in which these components stand to each other and which we may discover through comparison. As soon as such analyses have been made [p. 264] several times, results of the relating and comparing processe~s gained elsewhere can be employed in any particular case.
