228 Time, Space, and Causation. CHAP. 



theoretically, aware that there are three dimensions 

 in Space, and no more. 



The same kind of analysis applies to the relation 

 of Causation and Force. As Time is the abstract, or 

 absolute, which underlies all relations of succession, 

 and Space is the abstract which underlies all relations 

 of position, so Force is the abstract which underlies 

 all relations of Causation ; and as we acquire our idea 

 of Space by perceiving the relation of position between 

 objects, and that of Time by experience of the rela- 

 tion of succession among our feelings, so we acquire 

 that of Force by experience of the action on us of 

 the external world in such agencies as wind and rain, 

 and by consciousness of our own action in turn on 

 the external world, as when we throw a stone or light 

 a fire. 



In order to anticipate a possible difficulty, I may 

 remark that this conclusion leaves untouched the 

 question of the possibility of the existence of more 

 than three dimensions in Space. It is certain that 

 the universe of which we are part, exists and moves 

 in only three dimensions ; but I understand that 

 researches in imaginary geometry have shown the 

 supposition of four dimensions, or of any number up 

 to infinity, to be tenable without logical contradic- 

 tion. 



It is a mere statement of fact to say that Space, 

 Time, and Causation, are forms of thought : the ques- 

 tion is how they have become so. Kant's conclusion, 

 that they are ultimate facts of Mind and nothing more, 



