4 THEORETICAL BIOLOGY 



the horizontal rows the sounds would be arranged according 

 to octaves, while each vertical row would hold the sounds 

 of one octave. 



By means of such a piano we can most easily demonstrate 

 the twofold relationship which each local sign has to its 

 neighbours. For with the local signs two types of relation- 

 ship can be shown. If the nervous areas are stimulated 

 one after the other throughout the length of one of our limbs, 

 the local signs come into play in a definite and related series, 

 which, repeating itself with every lengthwise stimulation, 

 may lead to some confusion. Another type of relationship- 

 series appears when the stimulation acts transversely. These 

 two types are never confused with one another. 



Now, with normal stimulation, as, for instance, when you 

 press the ball of a finger on the edge of the table, the local 

 signs play a quite subordinate role to that of the touch- 

 qualities ; and, in virtue of this, their fixed relation-series can 

 the better be appreciated, for the touch-qualities have got no 

 arrangement of the kind. We might indeed go so far as to 

 say that the same touch-quality really always repeats itself, 

 and changes only in intensity. So we transfer the arrange- 

 ment of the local signs to the touch-qualities, and are enabled 

 thereby to feel that these are arranged not only step-wise 

 with relation to one another, but also in rows alongside one 

 another. 



And it is only now that we understand in its full signifi- 

 cance the profound truth of Kant's dictum that space is merely 

 a form of sense perception. For what enables us to apprehend 

 touch-sensations as extended is not the new quality of the 

 local signs, but the form of their arrangement, which is 

 extension itself. 



The existence of a quality which is merely consonant with 

 the local signs and yet independent of them, and which gives 

 information as to the place of stimulation, could be proved in 



