But such an increase in the number of beats in the rhythmic arrangement demands a certain exertion, and the length of the row that can be grouped together as one whole does not increase, but decreases. In these experiments a further remarkable quality of consciousness appears, which is closely connected to the rhythmical disposition of consciousness. The three degrees of emphasis, which the diagram of 4/4 time shows, form a maximum of differentiation which cannot be surpassed. Counting the unaccented beat as well, we arrive at a scale of intensity of four grades as the highest limit in the gradation of the intensity of impressions. This value clearly determines the rhythmical arrangement of the whole row, and with it the comprehension of this in consciousness, just as on the contrary the rhythm of the beats determines the number of gradations in intensity, which are necessary in the arrangement of the row of beats as supports for the comprehension by consciousness. Both factors therefore stand in close relationship to each other. The rhythmical disposition of consciousness demands certain limits for the number of grades of emphasis, and these on their part demand that specific rhythmical disposition which is peculiar to the human consciousness. The more extensive the rows of beats become, which we join together in the experiments described, the more clearly does another important phenomenon of consciousness appear. If we pay attention to the relation between a beat, perceived in a certain given moment, and one that has immediately preceded it, and if we further compare this latter with a beat further back in the row that is being grouped together as a whole, differences of a certain kind between all these impressions appear. They are quite different from the variations in intensity and emphasis. To describe them we do best to make use of expressions, which were first of all formed in all languages to describe the perception of visual impressions, where the same differences also appear and are relatively independent of differences in the intensity of light. These expressions are "clearness" and "distinctness." Their meanings almost coincide, but still they differ inasmuch as they denote different sides of the faculty of perception. "Clearness" refers more to the special constitution of the impression itself; "distinctness" to the relation of the impression to other impressions from which it seems to stand out. Let us transfer these conceptions in a generalised sense to the content of consciousness. One row of beats clearly shows in each of its separate elements the most varying degrees of clearness and distinctness. They all in a regular manner bear upon the beat that is affecting consciousness at the moment. This beat is the one that is most clear and most distinct. The ones immediately preceding are most like this one, whereas those that lie further back lose more and more in clearness. If the beat furthest