THE FACTS OF SCIENCE 67 



appeals to the world of phenomena — to immediate sense- 

 impressions — with the view of testing and verifying the 

 accuracy of its conceptions and inferences, the ultimate 

 basis of which lies, as we have seen, in such immediate 

 sense-impressions. Science deals with the contents of the 

 mind, the " inside " world, and the aim of its processes of 

 classification and inference is precisely that of instinctive 

 or mechanical association, namely, to enable the exertion, 

 best calculated to preserve the race and give pleasure to 

 the individual, to follow on the sense-impression with the 

 least expenditure of time and of intellectual energy. 

 Science is in this respect an economy of thought — a 

 delicate tuning in the interests of the individual of those 

 organs which receive sense-impressions and those which 

 expedite activity. The mind with scientific knowledge 

 brings with the greatest rapidity and with the least 

 intellectual strain fitting conceptions drawn from its store 

 of sense- impressions to bear on its immediate sense- 

 impressions, i.e. on the phenomenal world. 



Turn the problem round and ponder over it as we 

 may, beyond the sense -impression, beyond the brain 

 terminals of the sensory nerves we cannot get. Of wdiat 

 is beyond them, of " things-in-themselves," as the meta- 

 physicians term them, we can know but one characteristic, 

 and this we can only describe as a capacity for producing 

 sense-impressions, for sending messages along the sensory 

 nerves to the brain. This is the sole scientific statement 

 which can be made with regard to what lies beyond sense- 

 impressions. But even in this statement we must be 

 careful to analyse our meaning. The methods of classifica- 

 tion and inference, which hold for sense-impressions and 

 for the conceptions based upon them, cannot be projected 

 outside our minds, away from the sphere in which we 

 know them to hold^into a sphere which we have recognised 

 as unknown and unknowable. The laws, if we can speak 

 of laws, of this sphere must be as unknown as its contents, 

 and therefore to talk of its contents as prodticmg sense- 

 impressions is an unwarranted inference, for we are asserting 

 cause and effect — a law of phenomena or sense-impressions 



