_Series No. XII._--Both the figures of each pair in this series were linear, and presented the same extent of surface (granite-gray) with the same length of line. In other words, both figures were const.i.tuted of the same elements, and in both the corresponding lines ran in the same direction; but the lines in the one were connected so as to form a figure with a continuous boundary, while the lines of the other were disconnected, _i.e._, did not inclose a s.p.a.ce. The total length of line in each object was twenty centimeters, the breadth of the lines five millimeters. Both figures were arranged symmetrically with respect to a perpendicular axis.

[Ill.u.s.tration: FIG. 6.]

TABLE XII.

1 2 3 4 5 Indiv. Av.

L F L F L F L F L F L F I. 31.5 24 30 24.5 23.5 32 25.5 30.5 27 29.5 27.5 28.1 II. 55 55 56 56 56 56 56.5 56.5 54 54 55.5 55.5 III. 22 6 26.5 9.5 31.5 1.5 23 5.5 28.5 0 26.3 4.5 IV. 31 15 46.5 20.5 52 9.5 49 6 55 18 46.7 13.8 V. 56 54 56 56 56 56 56.5 56.5 55.5 55.5 56.0 55.6 VI. 33 30 34 39.5 31.5 29.5 26.5 32 26 31.5 30.2 32.5 VII. 55.5 49.5 56.5 38 54.5 35 57.5 32.5 38 27 52.4 36.4 VIII. 26.5 15.5 21.5 13.5 25 17 25.5 21 15 13.5 22.7 16.1 IX. 45.5 32.5 44.5 39 42.5 35.5 41.5 37.5 43 40.5 43.4 37.0 X. 29.5 23 36.5 16 23 28.5 35.5 16.5 29 23 30.7 21.4 XI. 52 8 49.5 19 45.5 25 43.5 21.5 15 31.5 41.1 21.0 39.77 28.41 41.77 30.18 40.10 29.60 40.05 28.73 35.10 29.50 39.32 29.26

L: Interrupted lines.

F: Figure with continuous boundary. (Figure in outline.)

General average: Lines, 39.32 sec.; figure, 29.26 sec.

The experiment was devised in further exploration of the effect of the line in ideation. The result fully bears out, when read in the light of the introspective notes, what has been said of the importance of the motor element in ideation. It might have been supposed, in view of the importance usually attached to unity or wholeness of impression in arresting and holding the attention in external perception, that the completed figure would have the more persistent image. The general averages, however, stand as follows: Interrupted lines, 39.32 seconds per minute; completed figure, 29.26 seconds per minute. The individual averages show slight variations from the tendency expressed in these figures, but the averages for the several pairs are all in harmony with the general averages.

The notes furnish the key to the situation: "I felt that I was doing more, and had more to do, when thinking of the broken lines." "The broken figure seemed more difficult to get, but to attract attention; continuous figure easy to grasp." "Felt more active when contemplating the image of the broken figure." "In the broken figure I had a feeling of jumping from line to line, and each line seemed to be a separate figure; eye-movement very perceptible." The dominance of the interrupted lines in ideation is evidently connected with the more varied and energetic activity which they excited in the contemplating mind. Apparently the attention cannot be held unless (paradoxical as it may sound) it is kept moving about its object. Hence, a certain degree of complexity in an object is necessary to sustain our interest in it, if we exclude, as we must of course in these experiments, extraneous grounds of interest. Doubtless there are limits to the degree of complexity which we find interesting and which compels attention. A mere confused or disorderly complex, wanting altogether in unity, could hardly be expected to secure attention, if there is any truth in the principle, already recognized, that the definite has in ideation a distinct advantage over the vague. Here again the notes suggest the method of interpretation. "The broken lines," says one, "tended to come together, and to take the form of the continuous figure." Another remarks: "The broken figure suggests a whole connected figure; the continuous is complete, the broken wants to be."

In virtue of their power to excite and direct the activity of the attention the interrupted lines seem to have been able to suggest the unity which is wanting in them as they stand. "The broken lines," says another, "seemed to run out and unite, and then to separate again"--a remark which shows a state of brisk and highly suggestive activity in the processes implied in attention to these lines. And a glance at the diagram will show how readily the union of the broken lines may be made. These were arranged symmetrically because the lines of the completed figures were so arranged, in order to equalize as far as possible whatever aesthetic advantage a symmetrical arrangement might be supposed to secure.

It thus appears that, whatever the effect in ideation of unity in the impression, the effect is much greater when we have complexity in unity. The advantage of unity is undoubtedly the advantage which goes with definiteness of impression, which implies definite excitations and inhibitions, and that concentration of energy and intensity of effect in which undirected activity is wanting. But a bare unity, it appears, is less effective than a diversified unity. To what extent this diversity may be carried we make no attempt to determine; but, within the limits of our experiment, its value in the ideational rivalry seems to be indisputable. And the results of the experiment afford fresh proof of the importance of the motor element in internal perception.

TABLE XIII.

1 2 3 4 5 Indiv. Av.

F V F V F V F V F V F V I. 25 29 26 29 29.5 26.5 25.5 30 24.5 31 26.1 29.1 II. 56 56 55 55 54 54.5 47.5 47.5 45 50 51.5 52.6 III. 2.5 5.5 2.5 8.5 6.5 5 16.5 9.5 17 15 9.0 8.7 IV. 48 48 31.5 31.5 31 46 51.5 51.5 35 52 39.4 45.8 V. 54 54 56.5 52 56 56 56 56 54 56 55.3 54.8 VI. 39 29 30 33.5 35.5 22.5 32.5 34 33.5 24.5 34.1 28.7 VII. 46 55 54.5 46.5 46.5 50 49.5 54 47 46 48.7 50.3 VIII. 9 14.5 23 20.5 23.5 22 18 14.5 16 17 17.9 17.7 IX. 43 43 46.5 46.5 45.5 45.5 43.5 43.5 46 47.5 44.9 45.2 X. 28 26.5 21 29.5 26.5 26.5 21.5 31.5 25 29 24.4 28.6 XI. 23.5 46 19.5 35.5 20 46 24 47.5 28.5 19.5 23.1 38.9 34.00 36.95 33.27 35.27 34.05 36.41 35.09 38.14 33.77 35.23 34.03 36.40

F: Figure (in outline). V: Vertical lines.

General average: Figure, 34.03 sec.; vertical lines, 36.40 sec.

_Series No. XIII._--In this series, also, both the figures of each pair were const.i.tuted of the same elements; that is to say, both were linear, and presented the same extent of surface (granite-gray), with the same length of line, the total length of the lines in each figure being twenty centimeters and the breadth of the lines being three millimeters. But while the lines of one figure were connected so as to form a continuous boundary, the lines of the other figure were all vertical, with equal inters.p.a.ces. And, as in the last preceding series, the two figures were formed by a different but symmetrical arrangement of the same lines.

As before, the advantage is on the side of the disconnected lines. In this case, however, it is very slight, the general averages showing 34.03 seconds for the completed figure, as against 36.40 seconds for the lines. This reduction in the difference of the averages is probably to be explained by the reduced complexity in the arrangement of the lines. So far as they are all parallel they would not be likely to give rise to great diversity of movement, though one subject does, indeed, speak of traversing them in all directions. In fact, the completed figures show greater diversity of direction than the lines, and in this respect might be supposed to have the advantage of the lines. The notes suggest a reason why the lines should still prove the more persistent in ideation. "The lines appealed to me as a group; I tended always to throw a boundary around the lines," is the comment of one of the subjects. From this point of view the lines would form a figure with a content, and we have learned (see Series No. VI.) that a s.p.a.ce with a varied content is more effective in ideation than a h.o.m.ogeneous s.p.a.ce of the same extent and general character. And this unity of the lines as a group was felt even where no complete boundary line was distinctly suggested. "I did not throw a boundary around the lines," says another subject, "but they had a kind of unity." It is possible also that from the character of their arrangement the lines reinforced each other by a kind of visual rhythm, a view which is supported by the comments: 'The lines were a little plainer than the figure;' 'figure shadowy, lives vivid;' 'the figure grew dimmer towards the end, the lines retained their vividness.'

On the whole, however, the chances are very nearly equal in the two cases for the recurrence of the image, and a comparison of this series with Series No. XII. cannot leave much doubt that the greater effectiveness of the lines in the latter is due to their greater complexity. In view, therefore, of the fact that in both series the objects are all linear, and that the two series differ in no material respect but in the arrangement of the disconnected lines, the circ.u.mstance that a reduction in the complexity of this arrangement is attended by a very considerable reduction in the power of the lines to recur in the image or idea is a striking confirmation of the soundness of our previous interpretation.

_Series No. XIV._--In this series full-faced figures (granite-gray) similar in character to those made use of in former experiments, were employed. The objects were suspended by black silk threads, but while one of them remained stationary during the exposure the other was lowered through a distance of six and one half centimeters and was then drawn up again. The object moved was first that on the right hand, then that on the left. As the two objects in each case were exactly alike, the comparative effect of motion and rest in the object upon the persistence in consciousness of the corresponding image was obtained. The result shows a distinct preponderance in favor of the moved object, which has an average of 37.39 seconds per minute as against 28.88 seconds for the stationary object. The averages for the pairs, as seen at the foot of the columns, all run the same way, and only one exception to the general tendency appears among the individual averages.

TABLE XIV.

1 2 3 4 5 Indiv. Av.

S M S M S M S M S M S M I. 22.5 28.5 25 30.5 24.5 28 28 27.5 25.5 31 25.1 29.6 II. 47.5 55 53 42 48.5 53.5 34.5 39.5 49 52 46.5 48.4 III. 3 18 7.5 8.5 0 7.5 0 3.5 0 4 2.1 8.3 IV. 45 45 33.5 51.5 11 50.5 11 50 8 52.5 21.7 49.9 V. 54.5 51 53.5 54.5 49 51 30.5 38.5 56 55 48.7 50.0 VI. 21 32.5 26 33 29.5 37.5 30 35 30 36 27.3 34.8 VII. 48 55 56.5 49 41.5 54.5 44.5 53 35.5 54 45.2 53.1 VIII. 10.5 20.5 20.5 25 6 33 12.5 29.5 19 18 13.7 25.2 IX. 37.5 43.5 34.5 45 36 47.5 30 47.5 29 48.5 33.4 46.4 X. 13 39.5 18 34 19 33.5 19 33 10.5 44 15.9 36.8 XI. 17.5 43.5 47.5 32 27.5 36 46 16.5 52 16 38.1 28.8

29.09 39.27 34.14 36.82 26.59 39.55 26.00 33.95 28.59 37.36 28.88 37.39

S: Refers to figure left stationary.

M: Refers to figure that was moved during exposure.

General average: S, 28.88 sec.; M, 37.39 sec.

The effectiveness of a bright light or of a moving object in arresting attention in external perception is well understood. And the general testimony of the subjects in this experiment shows that it required some effort, during the exposure, to give an equal share of attention to the moving and the resting object. Table IV., however, which contains the record of the observations in the white-gray series, shows that we cannot carry over, unmodified, into the field of ideation all the laws that obtain in the field of perception. The result of the experiment, accordingly, could not be predicted with certainty. But the course of ideation, in this case, seems to follow the same general tendency as the course of perception: the resting object labors under a great disadvantage. And if there is any force in the claim that diversity and complexity in an object, with the relatively greater subjective activity which they imply, tend to hold the attention to the ideated object about which this activity is employed, the result could hardly be other than it is. There can be no question of the presence of a strong motor element where the object attended to moves, and where the movement is imaged no less than the qualities of the object. In fact, the object and its movement were sometimes sharply distinguished. According to one subject, 'the image was rather the image of the motion than of the object moving.' Again: 'The introspection was disturbed by the idea of motion; I did not get a clear image of the moving object; imaged the motion rather than the object.' And a subject, who on one occasion vainly searched the ideational field for sixty seconds to find an object, reports: 'I had a feeling of something going up and down, but no object.' Clearly an important addition was made to the active processes implied in the ideation of a resting object, and it would be singular if this added activity carried with it no corresponding advantage in the ideational rivalry. In one case the ideas of rest and of movement were curiously a.s.sociated in the same introspective act. "The figure which moved,"

says the subject, "was imaged as stationary, and yet the idea of movement was distinctly present."

The reports as to the vividness of the rival images are somewhat conflicting. Sometimes it is the moving object which was imaged with the more vivid content, and sometimes the resting object. One report runs: "The moving object had less color, but was more distinct in outline than the stationary." Sometimes one of the positions of the moving object was alone represented in the image, either the initial position (on a level with the resting object) or a position lower down. On the other hand, we read: "The image of the moved object seemed at times a general image that reached clear down, sometimes like a series of figures, and not very distinct; but sometimes the series had very distinct outlines." In one case (the circle) the image of the figure in its upper position remained, while the serial repet.i.tions referred to extended below. This, as might be supposed, is the report of an exceptionally strong visualizer. In other cases the object and its movements were not dissociated: "The moved object was imaged as moving, and color and outline were retained." And again: "Twice through the series I could see the image of the moving object as it moved." "Image of moved object moved all the time."

TABLE XV.

1 2 3 4 5 Indiv. Av.

Gray Red Gray Yellow Gray Green Gray Blue Gray Violet Gray Colored.

I. 26 29 27.5 28.5 26.5 29 21.5 27.5 27.5 26.5 25.8 28.1 II. 35.5 36.5 45.5 53.5 53.5 53.5 53.5 53.5 55 55 48.6 50.4 III. 0 11 2.5 19 10.5 16 17.5 8.5 0 9 6.1 12.7 IV. 45 23.5 8 53.5 48 39 48 52 55.5 35 40.9 40.6 V. 55.5 55.5 42 53 50 56 52.5 50 44.5 56.5 49.1 54.2 VI. 22 33.5 29 36.5 28 43.5 26 37.5 39.5 29 28.9 36.0 VII. 38.5 39 56 56 49.5 54.5 47 47 45.5 50 47.3 49.3 VIII. 15 10.5 15 19.5 23 21 19.5 24 20.5 25 18.6 20.0 IX. 31.5 49 19 42.5 50 50 35.5 46 48 39 36.8 45.3 X. 19 33 14.5 37 29.5 23 17 37.5 23 31 20.6 32.3 XI. 11 49.5 8 51.5 9 43.5 35 43.5 24 47 17.4 47.0 27.18 33.64 24.27 40.95 34.32 39.00 33.91 38.82 34.82 36.64 30.90 37.81

General average: Gray, 30.90 sec.; colored, 37.81 sec.

_Series No. XV._--The figures in each pair of this series were full-faced, and of the same shape and size, but one was gray and the other colored, the gray being seen first to the left, and then to the right. The colors used were of Prang's series (Gray, R., Y., G., B., V.). In No. 1 the figures were in the form of a six-pointed star, and gray was compared with red. In No. 2 the figures were elliptical, and gray was compared with yellow. In No. 3 a broad circular band of gray was compared with the same figure in green. In No. 4 the figures were kite-shaped, and gray was compared with blue. In No. 5 a circular surface of gray was compared with a circular surface of violet. The objects compared were exposed at the same time, under the usual conditions.

As might perhaps be expected, the colored surfaces proved to be the more persistent in ideation, showing a general average of 37.81 seconds per minute as against 30.90 seconds for the gray.

The distinctness of the process of color apprehension is reflected in the notes: "In the colored images I find the color rather than the form occupying my attention; the image seems like an area of color, as though I were close to a wall and could not see the boundary;" and then we have the significant addition, "yet I feel myself going about in the colored area." Again: "In the gray the outline was more distinct than in the colors; the color seems to come up as a shade, and the outline does not come with it." Or again: "The gray has a more sharply defined outline than the color." This superior definiteness in outline of the gray figures is subject to exceptions, and one subject reports 'the green outline more distinct than the gray.' And even so brilliant a color as yellow did not always obscure the boundary: "The yellow seems to burn into my head," says one of the subjects, "but the outline was distinct." The reports in regard to this color (yellow) are in fact rather striking, and are sometimes given in terms of energy, as though the subject were distinctly conscious of an active process (objectified) set up in the apprehension of this color. The reports run: "The yellow has an expansive power; there seemed to be no definite outline." "The yellow seemed to exert a power over the gray to suppress it; its power was very strong; it seemed to be aggressive."

TABLE XVI.

1 2 3 4 5 a b a b a b a b a b I. 0 0 0 0 0 0 0 0 0 0 II. 43 41 33 51 19 31 32 41 20 18 III. 0 6 0 0 3 11 13 16 0 0 IV. 56 28 23 35 0 11 48 56 35 25 V. 56 55 44 44 57 30 39 32 34 30 VI. 14 8 12 12 11 5 35 12 9 6 VII. 52 54 56 56 51 47 56 57 47 26 VIII. 15 0 18 21 24 39 26 10 23 21 IX. 28 25 39 31 23 28 26 36 25 17 X. 0 0 0 0 0 0 0 0 0 0 XI. 52 45 41 48 7 39 50 36 48 22 35.11 29.11 29.55 33.11 21.66 26.78 29.55 26.91 21.91 15.00

_Series No. XVI._--The course of experimentation having shown the superior energy of lines, in comparison with surfaces, in stimulating, directing, and holding the attention, a series of figures was devised to test the question whether the direction of the lines would have any effect upon the length of time during which _both_ images of a pair of linear figures would be presented together. The materials used were granite-gray strips half a centimeter wide. The letters (_a_) and (_b_) at the heads of the columns refer to the same letters in the diagram, and distinguish the different arrangements of the same pair of objects. The figures in the body of the columns show only the length of time during which both images were reported present in consciousness together. At the foot of the columns are shown the averages for each pair. No general averages are shown, as the problem presented by each pair is peculiar to itself.

[Ill.u.s.tration: FIG. 7.]

The maximum is reached in No. 1_a_, where the angle has the arrowhead form and each angle points to the other. It should be remarked that the diagram is somewhat misleading in respect to the distance of the figures, which in this as in the other experiments was 25 cm. The figures therefore were far enough away from each other to be perceived and imaged in individual distinctness. But the 'energy' of the lines, especially where the lines united to form an acute angle, was often sufficient to overcome the effect of this separation, and either to bring the figures nearer together or to unite them into a single object. The notes are very decisive in this regard. A few of them may be cited: "The angles tended to join points." "The figures showed a tendency to move in the direction of the apex." "The angles (2_a_) united to form a cross." "When both figures (4_b_) were in mind I felt disagreeable strains in the eyeb.a.l.l.s; one figure led me to the right and the other to the left." The effect of the last-named figures (4_a_) seemed to be different from that of 1_a_ and 2_a_, though the apex of each angle was turned to that of the other in each of the three cases. "The two angles," says another subject, speaking of 4_a_, "appeared antagonistic to each other." It will be observed that they are less acute than the other angles referred to, and the confluent lines of each figure are far less distinctly directed towards the corresponding lines of the opposing figure, so that the attention, so far as it is determined in direction by the lines, would be less likely to be carried over from the one image to the other.

On the other hand, when the angles were turned away from each other the legs of the angles in the two figures compared were brought into closer relation, so that in 2_b_, for instance, the average is even higher than in 2_a_. Similarly the average in 3_b_, an obtuse angle, is higher than in 3_a_. The notes show that in such cases the contrasted angles tended to close up and coalesce into a single figure with a continuous boundary. "The ends (2_b_) came together and formed a diamond." "When the angles were turned away from each other the lines had an occasional tendency to close up." "There was a tendency to unite the two images (4_a_) into a triangle." "The two figures seemed to tug each other, and the images were in fact a little closer than the objects (4_a_)." "The images (4_a_) formed a triangle." So with regard to the figures in 5_a_. "When both were in the field there seemed to be a pulling of the left over to the right, though no apparent displacement." "The two figures formed a square."

The lowest average--and it is much lower than any other average in the table--is that of 5_b_, in which the contrasted objects have neither angles nor incomplete lines directed to any common point between the objects. In view of the notes, the tabulated record of these two figures (5_b_) is very significant, and strikingly confirms, by its negative testimony, what 1_a_ and 2_b_ have to teach us by their positive testimony. The averages are, in the three cases just cited: 1_a_, 35.11 seconds; 2_b_,33.11 seconds; 5_b_, 15 seconds per minute.

On the whole, then, the power of the line to arrest, direct, and keep the attention, through the greater energy and definiteness of the processes which it excites, and thereby to increase the chances of the recurrence and persistence of its idea in consciousness, is confirmed by the results of this series. The greatest directive force seems to lie in the sharply acute angle. Two such angles, pointing one towards the other, tend very strongly to carry the attention across the gap which separates them. (And it should be borne in mind that the distance between the objects exposed was 25 cm.) But the power of two incomplete lines, similarly situated, is not greatly inferior.

It thus appears that the attention process is in part, at least, a motor process, which in this case follows the direction of the lines, acquiring thereby a momentum which is not at once arrested by a break in the line, but is readily diverted by a change in the direction of the line. If the lines are so situated that the attention process excited by the one set is carried away from the other set, the one set inhibits the other. If, on the other hand, the lines in the one set are so situated that they can readily take up the overrunning or unarrested processes excited by the other set, the two figures support each other by becoming in fact one figure. The great importance of the motor elements of the attention process in ideation, and thus in the persistence of the idea, is evident in either phase of the experiment.