THE NATURE OF REALITY 459 



should this limit be included within the realm of data by 

 virtue of having been suggested in this forceful way? An ex- 

 treme phenomenalism would say, no; a moderate phenome- 

 nalism would be in doubt; a realism would say, yes. Keyser 

 deserves credit for having attempted to make as precise as 

 possible the character of the suggestion. Certainly a more 

 critical analysis of the notions of series and limits would 

 help to throw the problem in its proper light. But this is not 

 the place to make that analysis. Keyser's formulation at 

 least outlines the problem, and suggests the direction for 

 further consideration. 



What may be said, in conclusion, as to the general charac- 

 ter of these solutions to the problem of reality? They are 

 hardly such as to impress a critical mind, and one might 

 easily condemn them to oblivion on these grounds. But in 

 taking this attitude one should note two facts with reference 

 to them. The first is that they are commonly put forward 

 merely as speculative conclusions, having a greater rather 

 than a lesser degree of probability; they are not final solu- 

 tions but merely somewhat plausible suggestions. They 

 must, accordingly, be estimated from this point of view. 

 The second fact is that they do suggest further problems of a 

 more critical nature. It seems quite clear that the conclu- 

 sions considered in the foregoing pages can be either more 

 firmly established or greatly weakened by a more careful 

 analysis of the scientific knowing techniques in general, and 

 of symbols in particular. Hence recognition should be made 

 of the fact that the problem of the nature of reality, as the 

 other speculative problems, rests upon the more critical 

 problems of the philosophy of science. It seems likely, there- 

 fore, that the problems of the immediate future are the criti- 

 cal rather than the speculative ones. Fortunately, the atten- 

 tion of investigators has been increasingly directed in recent 

 years to problems of formal logic and the general theory of 

 symbols; to problems of actual scientific methodology; and 

 to problems of the foundations and interrelations of the 

 sciences. These offer great promise for the future. 



