getic
organism is the real a-logical thing-in-itself which I am compelled to
postulate in order to explain my perception of physical phenomena in the
light of my physical activity; _ago, ergo possum_.

We must not overlook the unique position in our Presentment occupied by
the visual presentation. Its universality, simultaneousness, minute
accuracy, quantifiability, etc., are such that it is really to the
visual Presentment that I refer all other elements in my
sense-experience. I think of them with reference to it. In connection
with it I mentally construct my world. I associate with some
modification of the visual presentation the phenomena resultant upon the
energetic activity of my own organism, and the other forces and
potential Energies which that activity reveals and suggests. It is thus
that I derive the compound idea of Body as consisting of Figure,
Extension, and Solidity. The continued appearance in my visual
presentation of the grey colour which I am now seeing is to me the sign
of the continued persistence of that potential Energy in virtue of which
I regard it as the appearance of a solid extended stone wall. Everything
is referred to the visual presentation, and it is in reference to it
that the mind works in constructing its world.

The whole theory of molecular action is a theory constructed in
reference to the visual presentation--the reality of which, strangely,
it seems to result in overthrowing. A born-blind man could never have
invented the conception of atoms or molecules. This is well worth
thinking over. The visual presentation is not really fundamental; and we
must undo the inversion induced by its great convenience whereby we
refer to it all the other elements of our sense-experience and conceive
of our activity and our whole actual world by reference to the visible
sign. It is in consequence of this reference to the visual that bodies
are thought of as discrete units, so that it is difficult to conceive
that the real thing in virtue of which we experience the perception of,
say, a heap of stones, is truly more or less potential Energy--just as
the continuous process of thought is very different from the disparate
symbols of speech.

I habitually refer to the visual extended image as the primary basis of
my idea of the world, or of any particular part of the world, such as my
dining-room. Why? Simply because, for the reasons already noted, the
sense of sight is the sense of universal refere