But another point of view asserts itself constantly in the results of S, and scatteringly in those of the others.  Analyzing at first only the results of S, we find that up to F. 140, with one exception, he places the open tunnel much farther out than the other; and from F. 140 on, nearer.  He says, F. 120, V. 185, ’After this there is too large a black space’; that is, in bringing the open tunnel in, he is evidently filling space.  But why does he put the open tunnel so far out?  It seems that he is governed by the desire for ease in the apperception of the two objects.  In his note for F. 80, V. 180, this point of view comes out clearly.  He thinks of the objects as being apperceived side by side with the space about each (which apparently takes on the character of its object), and then he seems to balance these two fields.  Cf.  F. 60, V. 195:  ’The closed tunnel allows the eyes to wander, and so it needs a bigger field on each side.’  Evidently there is an implication here of the idea of balance.  Cf. also F. 120:  ’The black tunnel harmonizes with the black to the right, and seems to correspond in distance and depth,’ while the closed tunnel ‘hangs together with the black on the left.’  In brief, the view of F. seems to be that the closed tunnel is less interesting, and partly because it ‘allows the eyes to wander,’ partly as compensation for the greater heaviness of the open tunnel, it takes with it a larger space than the open tunnel.  It is on the whole better to put them apart, because it is more difficult to apperceive them when close together, and so the open tunnel in the earlier choices must, of course, go farther from the center.  When these points conflict with the necessity of filling space, the open tunnel comes nearer the center.  In general, the notes which emphasize the difficulty of apperceiving the two pictures as flat and deep together accompany choices where the tunnel is put uniformly farther out, or symmetrically.  Cf. G, (1), (5); A, (1); M, F. 40, etc.

Thus we may continue to separate the two points of view, that of mechanical balance and that of another kind of balance, which we have known heretofore as ‘space-filling,’ made possible by the power of the center to give ‘weight,’ but which seems to be now more explicitly recognized as a balancing of ‘fields.’  At this point we need repeat only, however, that the suggestion of depth in the third dimension seems to confer ‘weight,’ ‘heaviness,’ ‘balancing power’ on its object.

Before making a general survey of the results of this chapter, it is necessary to consider a type of choice which has been up to this point consistently neglected—­that in which the variable has been placed on the same side of the center as the fixed object.  On the theory of balance, either in its simple mechanical form or in its various disguises, this choice would at first seem to be inexplicable.  And yet the subjects usually took special pleasure in this choice, when they made it at all.  These minus choices are confined to three or four subjects and to two or three experiments.  Exp.  I. (a) and (b) show the largest number.  We have: