SPACE AND GEOMETRY.
ON PHYSIOLOGICAL, AS DISTINGUISHED FROM GEOMETRICAL, SPACE.
THE SPACE OF VISION.
The sensible space of our immediate perception, which we find ready at hand on awakening to full consciousness, is considerably different from geometrical space. Our geometrical concepts have been reached for the most part by purposeful experience. The space of the Euclidean geometry is everywhere and in all directions constituted alike; it is unbounded and it is infinite in extent. On the other hand, the space of sight, or "visual space," as it has been termed by Johannes Miiller and Hering, is found to be neither constituted everywhere and in all directions alike, nor infinite in extent, nor un-. bounded.1 The facts relating to the vision of forms, which I have discussed in another place, show that entirely different feelings are associated with "up-ness" and "downness," as well as with "nearness" and "farness." "Rightness" and "leftness" are like-
1 These terms are used in Eiemann 's sense.
5om which the many divergent forms that the science of space has historically assumed, are thus shown forth with a distinctness and precision that in suggestiveness at least leave little to be desired.