OF NATURE. 605 



has even been held that these forces and masses are the 

 real objects of inquiry, and that, if once they were fully 

 explored, all the rest would follow from the equilibrium 

 and motion of these masses. A person who knew 

 the world only through the theatre, if brought behind 

 the scenes and permitted to view the mechanism of the 

 stage's action, might possibly believe that the real world 

 also necessarily had a machine-room, and that, if this 

 were once thoroughly explored, we should know all. 

 Similarly, we too should beware lest the intellectual 

 machinery, employed in the representation of the world 

 on the stage of thought, be regarded as the basis of the 

 real world. . . . Such an overestimate of physics, in 

 contrast to physiology, such a mistaken conception of the 

 true relations of the two sciences, is displayed in the 

 inquiry whether it is possible to explain feelings by 

 the motions of atoms ? Let us seek the conditions that 

 could have impelled the mind to formulate so curious a 

 question. We find in the first place that greater con- 

 fidence is placed in our experiences concerning relations 

 of time and space ; that we attribute to them a more 

 objective, a more real character than to our experiences 

 of colours, sounds, temperatures, and so forth. Yet, if 

 we investigate the matter accurately, we must surely 

 admit that our sensations of time and space are just as 

 much sensations as are our sensations of colours, sounds, 

 and odours, only that in our knowledge of the former we 

 are surer and clearer than in that of the latter. Space 

 and time are well ordered systems of sets of sensations." 

 Let us see what effect this modern analysis of the 

 work of science and the processes of scientific reasoning 



