SCIENCE AND NATURE 35 



an example which can easily be given. Every one who 

 has any sense-perceptions at all, and can come into any 

 contact with the external world, has the feeling that 

 events occur at different times and that some occur 

 before others. This is an example of a judgment concern- 

 ing which there appears to be the truest and most perfect 

 universal agreement. If one person A judges that an 

 event x occurs before an event y, then anyone else, how- 

 ever abnormal his sensations so long as he can experience 

 the events at all, will also judge that x occurs before 

 y ; he will never judge that x occurs after y. If the reader 

 considers this example, I think he will feel that in such a 

 judgment of the order in which events occur it is almost 

 inconceivable that there should be anything but the 

 most perfect universal agreement. Such judgment, 

 and such only, form the proper basis of science. 



However our objector may make a last stand. He 

 may say that, though it is barely conceivable that there 

 should be disagreement about such a matter, barely 

 conceivable events do sometimes occur. It is just 

 possible that disagreement might arise where now there 

 is the most perfect agreement ; what would science 

 do then ? The question is unanswerable. It is quite 

 impossible to say what we should do if the world was 

 utterly different from what it is ; and it would be utterly 

 different from what it is if there were not judgments 

 concerning which universal agreement is obtainable. 

 It would be a world in which there was no "external 

 world/' For though, as has been urged, the general 

 agreement on which popular ideas about the external 

 world is based is not always as perfectly universal as is 

 demanded by the criterion set up by science, a deeper 

 inquiry than we can under take here would show that 

 common sense, just as much as science, does employ 

 conceptions which would be meaningless if, in the last 

 resort and in some cases, perfectly universal agreement 



