US DISCOURSE ON THE STUDY 



CHAP. IV. 



OF THE OBSERVATION OF FACTS AND THE COLLECTION 

 OF INSTANCES. 



(109.) NATURE offers us two sorts of subjects of 

 contemplation in the external world, objects, and 

 their mutual actions. But, after what has been said 

 on the subject of sensation, the reader will be at no 

 loss to perceive that we know nothing of the objects 

 themselves which compose the universe, except 

 through the medium of the impressions they excite 

 in us, which impressions are the results of certain 

 actions and processes in which sensible objects 

 and the material parts of ourselves are directly 

 concerned. Thus, our observation of external nature 

 is limited to the mutual action of material objects 

 on one another; and to facts, that is, the associ- 

 ations of phenomena or appearances. We gain no 

 information by perceiving merely that an object is 

 black ; but if we also perceive it to be fluid, we 

 at least acquire the knowledge that blackness is 

 not incompatible with fluidity, and have thus made 

 a step, however trifling, to a knowledge of the more 

 intimate nature of these two qualities. Whenever, 

 therefore, we would either analyse a phenomenon into 

 simpler ones, or ascertain what is the course or law 

 of nature under any proposed general contingency, 

 the first step is to accumulate a sufficient quantity 

 of well ascertained facts or recorded instances, 



