THE DEFINITION OF REALITY 287 



justification the scientist would claim for his quest is not 

 very clear, because it is not within the province of science 

 to formulate such a claim. But certainly he makes 

 claims which do not rest on the aesthetic perfection of 

 the solution or on material benefits derived from scien- 

 tific research. He would not allow his subject to be 

 shoved aside in a symposium on truth. We can scarcely 

 say anything more definite than that science claims a 

 "halo" for its world. 



If we are to find for the atoms and electrons of the 

 external world not merely a conventional reality but 

 "reality (loud cheers)" we must look not to the end but 

 to the beginning of the quest. It is at the beginning that 

 we must find that sanction which raises these entities 

 above the mere products of an arbitrary mental exercise. 

 This involves some kind of assessment of the impulse 

 which sets us forth on the voyage of discovery. How 

 can we make such assessment? Not by any reasoning 

 that I know of. Reasoning would only tell us that the 

 impulse might be judged by the success of the adventure 

 — whether it leads in the end to things which really 

 exist and wear the halo in their own right; it takes us 

 to and fro like a shuttle along the chain of inference in 

 vain search for the elusive halo. But, legitimately or not, 

 the mind is confident that it can distinguish certain 

 quests as sanctioned by indisputable authority. We 

 may put it in different ways ;- the impulse to this quest 

 is part of our very nature; it is the expression of a 

 purpose which has possession of us. Is this precisely 

 what we meant when we sought to affirm the reality of 

 the external world? It goes some way towards giving 

 it a meaning but is scarcely the full equivalent. I doubt 

 if we really satisfy the conceptions behind that demand 

 unless we make the bolder hypothesis that the quest 



