LITMIR.BIZ

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arouse pretty well almost all the conceptions which we have ever at any time formed, and the blue object which we have in fact before our eyes and perceive, will, through this crowd of ideas which are not directly related to it, be neither interpreted nor explained.

      In order, however, that the association of ideas may fulfil its functions in the operations of the brain, and prove itself a useful acquisition to the organism, one thing more must be added, namely, attention. This it is which brings order into the chaos of representations awakened by the association of ideas, and makes them subserve the purposes of cognition and judgment.

      What is attention? Th. Ribot[74] defines this attribute as ‘a spontaneous or an artificial adaptation of the individual to a predominating thought’. (I translate this definition freely because too long an explanation would be necessary to make the uninitiated comprehend the expressions made use of by Ribot.) In other words, attention is the faculty of the brain to suppress one part of the memory-images which, at each excitation of a cell or group of cells, have arisen in consciousness, by way either of association or of stimulus-wave; and to maintain another part, namely, only those memory-images which relate to the exciting cause, i.e., to the object just perceived.

      Who makes this selection among the memory-images? The stimulus itself, which rouses the brain-cells into activity. Naturally those cells would be the most strongly excited which are directly connected with the afferent nerves. Somewhat weaker is the excitement of the cells to which the cell first excited sends its impulse by way of the customary nerve channels; still weaker the excitement of those cells which, by the same mechanism, receive their stimulus from the secondarily excited cell. That idea will be the most powerful, therefore, which is awakened directly by the perception itself; somewhat weaker that which is aroused by the first impression through association of ideas; weaker still that which the association in its turn involves. We know further that a phenomenon never produces a single stimulus, but several at once. If, for example, we see a man before us, we do not merely perceive a single point in him, but a larger or smaller portion of his exterior, i.e., a large number of differently coloured and differently illuminated points; perhaps we hear him as well, possibly touch him, and, at all events, perceive besides him somewhat of his environment, of his spacial relations. Thus, there arise in our brain quite a number of centres of stimulation, operating simultaneously in the manner described above. There awakes in consciousness a series of primary presentations, which are stronger, i.e., clearer, than the associated or consequent representations, namely, just those presentations which the man standing before us has himself aroused. They are like the brightest light-spots in the midst of others less brilliant. These brightest light-spots necessarily predominate in consciousness over the lesser ones. They fill the consciousness, which combines them in a judgment. For what we call a judgment is, in the last resort, nothing else than a simultaneous lighting up of a number of presentations in consciousness, which we in truth only bring into relation with each other because we ourselves became conscious of them at one and the same moment. The ascendency which the clearer presentations acquire over the more obscure, the primary presentations over derived representations, in consciousness, enables them, with the help of the will, to influence for a time the whole brain-activity to their own advantage, viz., to suppress the weaker, i.e., the derived, representations; to combat those which cannot be made to agree with them; to reinforce, to draw into their circuit of stimulation, or simply to arouse, others, through which they themselves are reinforced and secure some duration in the midst of the constant emergence and disappearance of representations in their pursuit of each other. I myself conceive the interference of the will in this struggle for life amongst representations as giving motor impulses (even if unconsciously) to the muscles of the cerebral arteries. By this means the bloodvessels are dilated or contracted as required,[75] and the consequent supply of blood becomes more or less copious.[76] The cells which receive no blood must suspend their action; those which receive a larger supply can, on the contrary, operate more powerfully. The will which regulates the distribution of blood, when incited by a group of presentations temporarily predominating, thus resembles a servant who is constantly occupied in a room in carrying out the behests of his master: to light the gas in one place, in another to turn it up higher, in another to turn it off partly or wholly, so that at one moment this, and at another that, corner of the room becomes bright, dim, or dark. The preponderance of a group of presentations allows them during their period of power to bring into their service, not only the brain-cells, but the whole organism besides; and not only to fortify themselves through the representations which they arouse by way of association, but also to seek certain new sense-impressions, and repress others, in order, on the one hand, to obtain new excitations favourable to their persistence—new original perceptions—and on the other hand, through the exclusion of the rest, to ward off such excitations as are adverse to their persistence.

      For instance, I see in the street a passer-by who for some reason arouses my attention. The attention immediately suppresses all other presentations which, an instant before, were in my consciousness, and permits those only to remain which refer to the passer-by. In order to intensify these presentations I look after him, i.e., the ciliary and ocular muscles, then the muscles of the neck, perhaps also the muscles of the body and of the legs, receive motor impulses, which serve the purpose only of keeping up continually new sense-impressions of the object of my attention, by means of which the presentations of him are continuously strengthened and multiplied. I do not notice other persons who for the time come into my field of vision, I disregard the sounds which meet my ears, if my attention is strong enough I do not perhaps even hear them; but I should at once hear them if they proceeded from the particular passer-by, or if they had any reference to him.

      This is the ‘adaptation of the whole organism to a predominant idea’ of which Ribot speaks. This it is which gives us exact knowledge of the external world. Without it that knowledge would be much more difficult of attainment, and would remain much more incomplete. This adaptation will continue until the cells, which are the bearers of the predominating presentations, become fatigued. They will then be compelled to surrender their supremacy to other groups of cells, whereupon the latter will obtain the power to adapt the organism to their purposes.

      Thus we see it is only through attention that the faculty of association becomes a property advantageous to the organism, and attention is nothing but the faculty of the will to determine the emergence, degree of clearness, duration and extinction of presentations in consciousness. The stronger the will, so much the more completely can we adapt the whole organism to a given presentation, so much the more can we obtain sense impressions which serve to enhance this presentation, so much the more can we by association induce memory-images, which complete and rectify the presentation, so much the more definitely can we suppress the presentations which disturb it or are foreign to it; in a word, so much the more exhaustive and correct will our knowledge be of phenomena and their true connection.

      Culture and command over the powers of nature are solely the result of attention; all errors, all superstition, the consequence of defective attention. False ideas of the connection between phenomena arise through defective observation of them, and will be rectified by a more exact observation. Now, to observe means nothing else than to convey deliberately determined sense-impressions to the brain, and thereby raise a group of presentations to such clearness and intensity that it can acquire preponderance in consciousness, arouse through association its allied memory-images, and suppress such as are incompatible with itself. Observation, which lies at the root of all progress, is thus the adaptation through attention of the sense-organs and their centres of perception to a presentation or group of presentations predominating in consciousness.

      A state of attention allows no obscurity to persist in consciousness. For either the will strengthens every rising presentation to full clearness and distinctness, or, if it cannot do this, it extinguishes the idea completely. The consciousness of a healthy, strong-minded, and consequently attentive man, resembles a room in the full light of day, in which the eye sees all objects distinctly, in which all outlines are sharp, and wherein no indefinite shadows are floating.

      Attention, therefore, presupposes strength of will, and this, again, is the property only of a normally constituted and unexhausted brain. In the degenerate, whose brain and nervous system are characterized by hereditary malformations or irregularities; in the hysterical, whom we have learnt to regard

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