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