52 THE GRAMMAR OF SCIENCE 



conceptions which are widely removed from sense-impres- 

 sions capable of immediate verification. The contents of 

 the mind at any instant are very far from being identical 

 with the range of actual or possible sense-impressions at 

 that instant. We are perpetually drawing inferences from 

 our immediate and stored sense-impressions as to things 

 which lie beyond immediate verification by sense ; — that 

 is, we infer the existence of things which do not belong to 

 the objective world, or which at any rate cannot be 

 directly verified by immediate sense -impression as be- 

 longing to it at the present moment. Strange as it may 

 seem, science is largely based upon inferences of this 

 kind ; its hypotheses lie to a great extent beyond the 

 region of the immediately sensible, and it chiefly deals 

 with conceptions drawn from sense-impressions, and not 

 with sense-impressions themselves. 



This point needs to be specially emphasised, for we 

 are often told that the scientific method applies only to 

 the external world of phenomena, and that the legitimate 

 field of science lies solely among immediate sense- 

 impressions. The object of the present work is to insist 

 on a directly contrary proposition, namely, that science is 

 in reality a classification and analysis of the contents of 

 the mind ; and the scientific method consists in drawing 

 just comparisons and inferences from the stored impresses 

 of past sense-impressions, and from the conceptions based 

 upon them. Not till the immediate sense-impression has 

 reached the level of a conception, or at least a perception, 

 does it become material for science. In truth, the field of 

 science is much more consciousness than an external world. 

 In thus vindicating for science its mission as interpreter of 

 conceptions rather than as investigator of a " natural law " 

 ruling an " external world of material," I must remind the 

 reader that science still considers the whole contents of 

 the mind to be ultimately based on sense-impressions. 

 Without sense-impressions there would be no conscious- 

 ness, no conceptions for science to deal with. In the next 

 place we must be careful to note that not every concep- 

 tion, still less every inference, has scientific validity. 



