EIDETIC IMAGERY AND TYPOLOGICAL METHODS IN PSYCHOLOGY
THE most important aspect of Eidetics--the theory of eidetic or perceptual images (Anschauungsbilder)--is that its development represents the first systematic application of typological methods of investigation. If these methods are consistently applied, they will, it seems, throw new light on many departments of our science. The new methods of approach, and the insight they give us, are best studied in the field of eidetic images, in which they originated. It is still occasionally assumed that eidetic imagery has been the exclusive material of our investigations. But in this book we shall have occasion to discuss investigations along other lines as well. Nevertheless, the new methods, and the insight they give us, are best described in the field in which they had their origin. For it is in this field that they have their most important applications, whose possibilities have by no means been exhausted, in spite of many years of labour.
Optical perceptual (or eidetic) images are phenomena that take up an intermediate position between sensations and images. Like ordinary physiological after-images, they are always seen in the literal sense. They have this property of necessity and under all conditions, and share it with sensations.