Page:Mind (Old Series) Volume 11.djvu/469

 468 A. BAIN : its own, besides the localisation accompanying every per- cept, whereby each excludes every other for the time. Here, however, arises a nice question. We can overlay a percept with an idea of a contradictory nature. We can look at a blue starry sky and imagine a gorgeous sunset, two things incompatible in actual perception. This shows, Mr. Ward thinks, that images float in a level of their own, quite above the presentation-continuum, and to this independent flux he would give the name of a " representation- or memory-con- tinuum," which he justifies later on. So much for the difference of presentation and image ; now for the connexion of the two. It is obvious that the presentation is the source of the image, and we are justified in assuming a transition from the one to the other. There is an intermediate stage, called by Fechner the memory- after-image, being the trace left by an impression after it has ceased. This may easily be distinguished from morbid persistence in a sensation itself, which has its own characters and contributes nothing to the formation of images or ideas. The evolving of the full-fledged image or idea from the memory-image is a stiff business, and not without uncer- tainties. The memory-image has already lost the essential characters of the impression, and especially the stubborn resistance to superposition of impressions ; for several may be in the field of consciousness together. It has made its mark as a thing persisting apart from its original presenta- tion, and what we need farther is a confirmation and deepening of this by subsequent renewals. What happens, then, on a second presentation, which also leaves its memory- image to fuse with the first ? Here Mr. Ward speaks in metaphors that are not quite clear. The revival of the image is not another birth, whatever that may mean. There is, in the case of an identical image, assimilation or recogni- tion, which precludes individual distinctness. If the second impression occurred in identical surroundings there would be no sense of distinctness ; when the surroundings are changed there is sense of distinctness; nevertheless, repeti- tion brings confirmation, being the case of similarity working in diversity. On the whole I call this an extremely laboured attempt to bring out the simple result of confirmation of images by repeated occurrence, there being more or less of identity in their accompaniments. The author is now brought face to face with "Menial Association," although his treatment is avowedly cursory. He appears to join the small company that would reduce the two principles of Contiguity and Similarity to one.