ur apprehension of the various visual sensations
depends on the presence and particular location of this small tangible
body. We find that the whole array of visual phenomena disappear when it
is tactually covered, that they reappear when it is reopened, and so
forth. Thus we come in some way to associate vision with it--not as
colour, however, not as visual sensation. We regard the organ and its
dispositions merely as a general condition regulating the apprehension
of the visual sensations, and no more.

Thus, by attending to the two associations that occur,--the association
(in place) of visual sensations with tangible bodies that _are not_ the
eye; and the association (in place) of vision with a small tangible body
that _is_ the eye--the eye regarded as the condition on which the
apprehension of these sensations depends; by attending to these, we can
understand how a protensive interval comes to be recognised between the
organ and its objects. By means of the touch, we have associated the
sensations of vision with tangible bodies in one place, and the
apprehension of these sensations with a tangible body in another place.
It is, therefore, impossible for the sight to dissolve these
associations, and bring the sensations out of the one place where they
are felt, into the other place where the _condition_ of their
apprehension resides. The sight is, therefore, compelled to leave the
sensations where they are, and the apprehension of them where it is; and
to recognize the two as sundered from each other--the sensations as
separated from the organ, which they truly are. Thus it is that we would
explain the origin of the perception of distance by the eye; believing
firmly that the sight would never have discerned this distance without
the mediation of the touch.

Rightly to understand the foregoing reasoning--indeed to advance a
single step in the true philosophy of sensation--we much divest
ourselves of the prejudice instilled into us by a false physiology, that
what we call our organism, or, in plain words, our body, is necessarily
_the seat_ of our sensations. That all our sensations come to be
associated _in some way_ with this body, and that some of them even come
to be associated with it _in place_, is undeniable; but so far is it
from being true, that they are all essentially implicated or
incorporated with it, and cannot exist at a distance from it, that we
have a direct proof to the contrary in our sensations of