The importance of these results as to the scope of consciousness and of attention does not lie merely in the fact that we are able to state the relation of both in values that can be expressed in figures. Above all, our results give us an important insight into the relations between those elements that stand in the focus of attention and those that belong to the wider field of consciousness. In order, then, to denote clearly the most important results that have come to light in these experiments, let us use two short expressions for the two processes of the entrance into consciousness, and of the elevation into the focus of attention—two expressions that were first of all introduced by Leibnitz in a similar sense. We shall call the entrance into the large region of consciousness—apprehension, and the elevation into the focus of attention—apperception. We shall take no account of the philosophical meanings, in which Leibnitz uses these expressions in his theory of monads. We shall use these expressions purely in their empirical and psychological sense. Accordingly we understand by apprehension simply the entrance of some content into consciousness—an entrance that can be in fact proved, and by apperception the grasping of this by the attention. The apprehended content is that of which we are more or less darkly aware; it is always, however, above the threshold of consciousness. The apperceived content is that of which we are clearly aware, or, keeping to the figure of speech of a threshold, that which lies above the narrower threshold of attention. We can further define the relation between these two regions of consciousness. If the apperception is directed to one isolated element, the rest, the merely psychically apprehended elements, disappear as if they were non-existent. On the other hand, if the apperceived content is bound to certain merely apprehended elements of consciousness, it is combined into one total apprehension, which is only limited by the threshold of consciousness itself. In close relationship with this stands the fact that the scope of apperception is a relatively limited and constant one, and that the scope of apprehension is not only larger, but also much more variable. And, as we have clearly seen from our comparison of simple and complex rhythmical rows, it varies according to the scope of the psychical complexes that are united together into one whole. Thereby the difference between the merely apprehended and the apperceived parts of such a whole by no means disappears. For it is only a limited part of this latter that lies within the focus of attention, as has been strikingly shown in reading experiments, where we can vary single and merely apprehended parts of a word, without thereby disturbing the comprehension of the total complex. To use a picture which is itself an example of this phenomenon, we may say that that wider darkly apprehended content stands in the same relation here as the chords of the piano accompaniment to the voice of the singer. Slight variations in the former are mostly unobserved, so long as the guiding voice is correct in pitch and rhythm. On the other hand, the impression of the whole would be feeble if the accompaniment was wanting.
In this relationship between the apprehended and apperceived content of consciousness another factor appears, which brings to light the great importance of the processes of apperception. We started out from the fact that it was extremely difficult to apprehend with absolute uniformity a row of identical beats, since we are always inclined to accentuate certain beats. This phenomenon is clearly connected with a fundamental characteristic of apperception, which intervenes in all processes of consciousness. We know, from ordinary life, that we are not able to direct our attention perfectly steadily and uniformly to one and the same object. When we attempt to do this, we notice that a continual change takes place in the apperception of the object in question. At times the attention turns towards the object most intensively, and at times its energy flags. Where the conditions remain uniform, this change gradually becomes regular and periodic. The rise of such a process is of course materially assisted, if the outside impressions themselves, to which our attention is directed, possess a regular periodicity. This is the case in a high degree with a row of beats. And so it happens that those oscillations of apperception are directly adjusted to the periodicity of the impressions. Therefore we emphasise an impression that coincides with a rise in the apperception wave, so that the beats which are in fact uniform become rhythmically arranged. The manner of this arrangement depends to a certain degree upon our own choice, and also upon the extent in which we are trying to combine the single impressions into a whole. If the beats follow each other very quickly, our endeavour to combine leads us easily into complicated rhythmical arrangements, as we have in fact noticed above. With other and especially with simultaneous impressions similar relations between the apperceived and the merely apprehended content of consciousness arise, but in varying form according to the sense in question. For example, if we expose a very short word in our reading experiments, the whole is easily apprehended at one glance. If, however, we expose a long word, e.g. "miscellaneousness," we notice at once, even by direct observation, that the apprehension time is a little longer and that it really is made up of two or three very rapid and successive acts of apperception, and these acts may last longer than the actual time the impression is affecting consciousness. This succession is seen more clearly, if instead of a word we expose a sentence of about the same length as the following:—
"Honesty is the best policy."
Here the breaking up of apperception into successive acts is materially assisted by the divisions of the words. With such a sentence we observe as a rule three successive acts of apperception, and it is the last that combines the whole into one unified thought. In such a case this is only possible as long as the preceding parts of the sentence from the last apperception remain in the field of consciousness. If the sentence is so long that this cannot happen, then the same thing occurs as we have observed with rhythmical rows of beats, that have passed the limits of possible rhythmical arrangement. We can only combine a part of such a successively exposed whole into one conclusive act of apperception. It is obvious therefore that the two phenomena, the apprehension of connected beats and of connected words and sentences, are essentially the same. The only difference consists in the fact that in the first case the apperceived impression is connected with the preceding one, that has retreated into the apprehension field, by means of the rhythmical arrangement, whereas the connection in the second case is brought about by means of the sense that binds the word or the parts of the word together. The process consists by no means of a mere successive apperception of the parts. These have already disappeared out of the apperception and have become merely apprehended elements, when they are combined into one whole along with the last apperceived impression. This act of combination is itself a uniform and instantaneous act of apperception. From this we see that, in all cases of a combination of a larger complex of elements, apperception is the function that unites these elements, and that in general it always combines directly apperceived parts of the whole with the merely apprehended parts that stand in connection. And so the great importance of the relations between these two functions of apperception and of apprehension lies precisely in the great change of these relations and in their adjustment to the needs of our psychical life, which finds expression in this change of relation to each other. At times the apperception concentrates upon a very narrow region, in order completely to free itself from the enormous manifoldness of incoming impressions. At other times, with the help of its capacity for grouping together successive elements which arises from the oscillating nature of its function, it winds its threads through a wide web of psychical contents, that stretches over the whole field of consciousness. Through it all apperception remains the unifying function which binds that manifold content into one ordered whole. Contrasted with it and subordinate to it, and in a certain sense acting as centrifugal forces, are the processes of apprehension, which with apperception together form the whole of our psychical life.
[CHAPTER II]
THE ELEMENTS OF CONSCIOUSNESS
In our last chapter we have discussed the general and formal characteristics of consciousness. These have appeared to us in the scope of consciousness, in the different grades of clearness and distinctness of its content, and lastly, connected with this, in the relations of apprehension and apperception. The next question that immediately presents itself is: Of what kind is the specific content that appears to us in these forms? The answer to this question includes the task of explaining the ultimate parts of this content, that cannot be further disintegrated. Such ultimate parts are generally called elements. Now it is one of the first tasks of each science, that deals with the investigation of empirical facts, to discover the elements of the phenomena. Its second task is to find out the laws according to which these elements enter into combinations. The whole task of psychology can therefore be summed up in these two problems: (1) What are the elements of consciousness? (2) What combinations do these elements undergo and what laws govern these combinations?
In contradistinction to the elements of consciousness let us call any combination of such elements a psychical compound. The relation of the two to each other can be at once made clear by the examples that lie at hand. Let us return to our metronome. If we let one single beat work upon consciousness and then immediately arrest the pendulum, we have a psychical element. Such a beat cannot in general be further disintegrated if we, as can easily be done in such a case, abstract from the fact that we hear it from some special direction in space, &c. If, on the other hand, we let two beats work, they constitute at once a psychical compound. This becomes always more complex, the more such beats we combine into a row, and the more we increase this complication by different degrees of accentuation, as in the examples of 2/8 and 4/4 time described above. Such an element of consciousness as the single beat is called a sensation, a combination of elements into rhythms of more or less complicated constitution is called an idea. Even at the present time many psychologists use the word "idea" only for a complex that does not arise from direct outward impressions, i.e. only for so-called "memory images." For ideas formed by outward sense impressions they generally use the word "perception." Now this distinction is psychologically of absolutely no importance, since there are really no valid differences between memory ideas and so-called sense-perceptions. The memory ideas of our dreams are in general quite as lively as sense impressions in the waking state, and it is for this reason that they are often held to be really experienced phenomena. The word "idea" denotes well the essential characteristic of all these complexes. The idea (Greek ιδεα) is the form or appearance of something in the outer world. In the same sense, as belonging to the outer world, we speak of the sensations and their complexes arising in our own body as organic sensations, because we locate them in out own body, e.g. the sensations of fatigue of our muscles, the pressure and pain sensations of the inner organs, &c. The relatively uniform elements of touch and organic sensations are distributed among the sensations of pressure, warmth, cold, and pain. In contra-distinction to these, the special senses of hearing, seeing, smelling, and tasting present an abundance of sensations, each of which, according to its peculiar constitution, is called a quality of sensation. Each such quality is besides variable in its intensity. We can, for example, produce a certain beat in very variable intensities, while the quality remains the same.