vi THE EMPIRICAL 



of perception can diagnose certain symptoms, make a fair 

 prognosis of the course of events, and apply palliatives or 

 even remedies with a greater or less degree of practical 

 success. The microscope reveals germs, and modifications 

 of cell tissues, chemistry traces actions and reactions all 

 invisible to common perception and all essential to a true 

 understanding of the matter. Whether the 'scientific' 

 account of causation is or can be adequate is a further ques- 

 tion which for the moment we do not raise. Enough is 

 known however to prove that even for the inanimate world 

 the working of causation is definitely not discoverable on 

 the plane of common sense. c Man joins and disjoins 

 bodies ; the rest nature transacts within.' Thus was the 

 measure of empirical knowledge and its practical application 

 adequately and succinctly described. And if this limitation 

 is true of the material order with its relative simplicity, 

 still more is it true of life and consciousness. Man knows 

 little of himself, but he knows enough to justify the broad 

 truth of the metaphor used above, that the sphere of con- 

 sciousness is but an illuminated spot on the surface of a 

 deep sea. 



But the forces within the depths are all the time at work. 

 They direct our movements and give form to our thought. 

 Nor are we in fact cut off from the knowledge of them by 

 any impassable barrier like that which in some metaphysical 

 systems separates appearance from reality. As the light 

 gathers in intensity and concentration it penetrates here and 

 there below the surface. But with regard to our know- 

 ledge of underlying forces we may usefully distinguish 

 three phases. In the first place, to begin with that which is 

 last in order of development but most intelligible in the 

 order of logic, we might attain to a clear and untroubled 

 vision of the forces as such. This would involve an en- 

 largement of our experience as well as an improvement of 

 our methods, of which we shall have to speak. In the 

 terms of our metaphor it would imply that the light had 

 penetrated below the surface to the depths. But in the 

 second place and short of this we may have an obscure and 

 imperfect glimpse of underlying realities. We may have 

 a sense that they are there without knowing what they are > 



