396 THE BODY AT WORK 



have discovered to me the fact that the designs on a wall- 

 paper succeed one another with unbroken regularity. Fixing 

 my gaze on one of them, I cannot by any effort of attention 

 efface the pattern which happens to be focussed on the blind 

 spot. I know that I shall see it the instant that I move the 

 eye. If I let my eye roam until the face of my wife falls on 

 the blind spot, its image disappears. I know its lineaments 

 far better than I know the pattern on the wall-paper, but I 

 cannot fill it into the picture. Her hands are visible, and the 

 work which is resting in her lap, but in a mysterious way the 

 background draws together where the face should be. My 

 mind refuses to pass a false judgment ; but it also refuses to 

 see that there is a gap. 



This exceedingly instructive observation teaches the rela- 

 tivity of sensations. It shows that a sensation has no objec- 

 tive value until judgment has been passed upon it by the 

 mind. The meaning of this we express in figurative language, 

 none other being available. We speak of a new sensation as 

 being compared with sensations previously received taken 

 into the picture-gallery of the mind, and placed in its due 

 position amongst the infinitely numerous records which are 

 stored there. If we try to make a nearer approach to cor- 

 relating physical with psychical activity, we say that sensa- 

 tion has no value save that which it acquires from its temporal 

 relation in the sequence of sensations to which attention is 

 directed, and that this value depends upon the relation which 

 similar sensations have possessed in former sequences. There 

 is no gap in binocular vision. An object focussed on the 

 inner (nasal) side of the right eye, where the blind spot is 

 situate, is focussed on the outer (temporal) side of the left eye. 

 The left eye sees the object to which the right eye is blind. 

 Since we have almost invariably used two eyes in the past, 

 experience teaches that there is no gap in the field of vision. 

 Hence the new group of sensations which alleges that there is 

 a gap must be corrected. The field must be filled up in the 

 way which experience shows to be most likely. The retina is 

 a sheet of rods and cones, each of which has a nervous con- 

 nection with the brain proper to itself. The retinal field 

 is associated with the brain-field. But this does not imply 

 that we may think of the mind as having a spatial distribution 



