68 
C. L. Herrick 
O + The dog whose vestigial image is repeatedly revived is 
not conceived of as a series of dogs or the same dog at different 
times: it is simply ^That dog;’’ but if the dog comes into my 
field of view, it is the same dog seen again or recognized. If I 
view an object in motion, it may produce one of two effects: 
if it passes too rapidly to be accommodated for, it produces the 
effect of changing position without change of time (extension). 
If the motion is slower, the jerky motion of the eyeball in 
accommodation produces a succession of images. The hiatus 
between these images is subjectively filled and we get the 
concept of continuous motion. The modalities of presentation 
here noticed are, then, (1) position (the act of positing), (2) 
absence, (3) recognition, (4) distinctness, (5) succession. In the 
higher sphere of judgment these become (1) existence, (2) nega- 
tion, (3) identity, (4) difference, (5) time. . The difference between 
the two categories is that one has a particular the other a general 
application. 
A synthesis of a visual impression gives us position (place). 
A synthesis of several places having an identical content gives 
us the idea of extension and thence figure, etc. The final syn- 
thesis results in the universal — space. In time the vestigial 
predominates; in space, the objective. Both are, in a sense, the 
necessary forms of our thinking, but the necessity is not an 
inexplicable or arbitrary one. It inheres in the nature of the 
presentative process and the synthetic necessities of thought. 
It may not be necessary to illustrate further. We have gone 
thus far into detail simply to indicate the way in which the dun- 
damental postulates are applicable to the problems of psychology 
and metaphysics. Everything could not be said in any one of 
cases cited. Enough has been said to show what further use 
could be made of the idea of energy. 
Psychologically speaking, space is certain stresses and strains, 
certain tensions in the effort to move. It is a question of posi- 
tion with respect to my organism as a center. Our primary 
experience of space is angular. 
Visual, i. e., retinal, space is in two dimensions. Such space is 
closed. Our visual life is in one surface only. The eye does not 
shoot forth visual tentacula in search of the object as the ancients 
supposed. 
We gain the idea of the third dimension only by going toward 
