Thoughts and Notes on Cognition - Understanding Understanding: Essays on Cybernetics and Cognition - page 181

2.2 This expression shows that neither the modality of the agent, nor
its parametric characteristic, nor reference to environmental point x is
encoded in the receptor's response, solely some clues as to the presence of
a stimulant for receptor r x are given by its activity r x .
2.21 Since all receptors of an organism respond likewise, it is clear that
organisms are incapable of deriving any notions as to the “variety of envi-
ronmental features,” unless they make reference to their own body by uti-
lizing the geometrical significance of the label x of receptor r x which reports:
“so and so much (r=r 1 ) is at this place on my body (x=x 1 ).”
2.22 Moreover, it is clear that any notions of a “sensory modality”
cannot arise from a “sensory specificity,” say a distinction in sensitivity
regarding different parameters p 1 and p 2 , or in different sensitivities s 1
and s 2 for the same parameter p , for all these distinctions are “integrated
out” as seen in expression 2.12. Consequently, these notions can only
arise from a distinction of the body-oriented loci of sensation x 1 and x 2 .(A
pinch applied to the little toe of the left foot is felt not in the brain but at
the little toe of the left foot. Dislocating one eyeball by gently pushing
it aside displaces the environmental image of this eye with respect to the
other eye.)
2.23 From this it becomes clear that all inferences regarding the envi-
ronment of W must be computed by operating on the distribution function
r x . (It may also be seen that these operations w ij are in some sense coupled
to various sensitivities s i [x, p j ].)
2.24 This becomes even more apparent if a physical agent in the envi-
ronment produces “actions at a distance.”
2.241 Let g ( x , p ) be the environmental distribution of sources of the
agent having parametric variety ( p ); let R be the distance between any point
x in the environment and a fixed point x 0 ; and let F( R ) be the distance func-
tion by which the agent loses its intensity. Moreover, let the point x 0 on the
body of an organism coincide with x 0 , then the stimulus intensity for recep-
tor r x0 is (Fig. 6):

( )

Ú

( ) ( )

Sx p , = F x x gx pdx - ,

0 0

postition

sensory field

and its response is

∫ ( ) r x FS

0 , position x 0 , position

compare with 2.12).
2.242 Again this expression shows suppression of all spatial clues,
save for self-reference expressed by the bodily location x 0 of the sensation
and by the position of the organism as expressed by the limits of the inte-
gral which can, of course, only be taken over the sensory field “seen” by
receptor cell r x0 (Fig. 6).
2.25 Since r x gives no clues as to the kind of stimulant ( p ), it must be
either x, the place of origin of the sensation, or the operation w(r x ), or both
that establish a “sensory modality.”