SPACE, TIME, MATTER, MOTION, AND FORCE. 173 



tion of such impressions, differing in kind and degree, 

 would give the materials for the establishment of rela- 

 tions, that is, of thought. And if such relations differed 

 in their forms as well as in their contents, the impressions of 

 such forms would be organized simultaneously with the 

 impressions they contained. Thus all other modes of con- 

 sciousness are derivable from experiences of Force; but 

 experiences of Force are not derivable from anything else. 

 Indeed, it needs but to remember that consciousness consists 

 of changes, to see that the ultimate datum of consciousness 

 must be that of which change is the manifestation ; and that 

 thus the force by which we ourselves produce changes, and 

 which serves to symbolize the cause of changes in general, 

 is the final disclosure of analysis. 



It is a truism to say that the nature of this undecom- 

 posable element of our knowledge is inscrutable. If, to use 

 an algebraic illustration, we represent Matter, Motion, and 

 Force, by the symbols a?, y, and z / then, we may ascertain 

 the values of x and y in terms of z / but the value of z can 

 never be found : z is the unknown quantity which must for 

 ever remain unknown; for the obvious reason that there is 

 nothing in which its value can be expressed. It is within 

 the possible reach of our intelligence to go on simplifying 

 the equations of all phenomena, until the complex symbols 

 which formulate them are reduced to certain functions of 

 this ultimate symbol; but when we have done this, we have 

 reached that limit which eternally divides science from 

 nescience. 



That this undecomposable mode of consciousness into 

 which all other modes may be decomposed, cannot be itself 

 the Power manifested to us through phenomena, has been 

 already proved ( 18). We saw that to assume an identity 

 of nature between the cause of changes as it absolutely ex- 

 ists, and that cause of change of which we are conscious 

 in our own muscular efforts, betrays us into alternative im- 

 possibilities of thought. Force, as we know it, can be re- 



