It follows that discrimination between simple and composite feelings in the sphere of affective qualities, can not be carried out. The feeling that corresponds to a particular sensation, is as a rule, for the reasons given, a product of the fusion of several simple feelings, though it is still as irreducible as a feeling of originally simple nature (cf. §12, 3). A further consequence is that the neutral middle between opposite affective qualities, can be actually found in experience only in the special cases where the affective tone of a particular sensation corresponds to the neutral middle of all [p. 80] the dimensions to which it belongs. This special condition is obviously fulfilled for the many-dimensional sensational systems, especially those of sight and hearing, in just the cases in which it is of special practical value for the undisturbed occurrence of affective processes. In the one case, sensations of medium brightness and those of the low grades of chromatic saturation approximating them, in the other, the auditory impressions of our ordinary environment, which are between a tone and noise in character (as, for example, the human voice), form the neutral indifference-zones of affective quality. On both sides of these zones arise the more intense affective tones of the more marked sensational qualities. The existence of such indifference-zones makes it possible for the complex feelings which correspond to the various combinations of these, sensational qualities, to develop almost independently, without reference to the accompanying sense-feelings.
5. The variations in affective quality and intensity that run parallel to the grades of sensational intensity, are much simpler. They can be most clearly seen in the homogeneous sensational systems of the general sense. Each of these systems is of a uniform quality throughout, and can be fairly well represented geometrically by a single point, so that the only possible sensational changes are those of intensity, and these can be attended only by a one-dimensional series of affective changes between opposites. The neutral indifference zone is, accordingly, always easy to observe in these cases. It corresponds to the medium sensations of pressure, hot, and cold, that are connected with the normal, medium intensity of ordinary sense-stimuli. The simple feelings on both sides of this zone exhibit decidedly opposite characters, and can, in general, be reckoned, on the one side, to pleasurable feelings, on the other, to unpleasurable (v. inf. 6). The unpleasurable feelings are the only ones that can be [p.
81] produced with certainty, by increasing the intensity of the sensation.
Through habituation to moderate stimuli, such Iii expansion of the indifference-zone has taken place in these systems of the general sense, that when the stimuli are weak, as a rule only a succession of sensations very different in intensity or quality, can produce noticeable feelings. In such cases, feelings of pleasure always correspond to sensations of medium intensity.
The regular relation between sensational intensity and affective tone, can be better observed without this influence of contrast, in the case of certain sensations of smell and taste. At first a pleasurable feeling arises with weak sensations and increases with the increasing intensity of the sensations to a maximum, then it sinks to zero with a certain medium sensational intensity, and finally, when this intensity increases still more, the feeling becomes unpleasurable and increases until the sensational maximum is reached.
6. The variety of simple affective qualities is exceedingly great, much greater than that of, sensations. This is due to two facts. First, every sensation of the many-dimensional systems 'belongs at once to several series of feelings. Secondly, and this is the chief reason, the different compounds arising from the various combinations of sensations, such as intensive, spacial, and temporal ideas, and also certain stages in the course of emotions and volitions, have corresponding feelings, which are, as above remarked (p. 76), irreducible, and must therefore be classed among the simple feelings.
It is greatly to be regretted that our names for simple feelings are so much more hazy than those for sensations. The proper nomenclature of feeling is limited entirely to the expression of certain general antitheses, as pleasurable and unpleasurable, agreeable and disagreeable, grave and gay, excited and quiet, etc. These designations are usually based on the [p. 82] emotions into which the feelings enter as elements, and are so general that each includes a large number of simple feelings of very different character. In other cases, complex ideas whose affective character is similar, are used in describing the feelings connected with certain simple impressions, as, for example, by Goethe in his description of the affective tone of colors, and by many musical writers in describing the feelings accompanying clangs. This poverty of language in special names for the feelings, is a psychological consequence of the subjective nature of the feelings. All the motives of practical life which give rise to the names of objects and their attributes, are here wanting. To conclude, for this reason, that there is a corresponding poverty of simple affective qualities themselves, is a gross psychological mistake, which is furthermore fatal since it makes an adequate investigation of the composite affective processes impossible from the first.