EXPLANATION OF RESULTS. 449 



must neither contain too much information nor too little. 

 If they contain too much, the excess is uncertain, and may 

 be entirely false ; and if they include too little, they do 

 not render manifest the whole amount of truth warranted 

 by the evidence. 



Quickness in explaining phenomena correctly depends 

 also upon a capacity for estimating the relative degrees of 

 generality and frequency of occurrence of different pheno- 

 mena. There are common causes and unfrequent ones ; 

 usual impurities in substances, and rare ones ; and other 

 circumstances being alike, the more frequent the existence 

 of a substance or action, the more likely is it to be the 

 cause of a newly-observed phenomenon. Success in ex- 

 plaining phenomena manifestly also depends, to a large 

 extent, upon the intensity and amount of thought be- 

 stowed upon each particular question. 



The explanation of results and of scientific facts in 

 general is a complex process, and often extremely dim- 

 cult. It consists in showing the various similarities of 

 the fact or phenomenon to other ones, also its cause, and 

 the various true relations of it to all the different circum- 

 stances or phenomena which precede, accompany, or follow 

 it. To ascertain all these usually requires a scientific 

 research. An isolated fact or phenomenon of a novel 

 kind, cannot be fully explained without a proper and 

 sufficient investigation, because the explanation requires 

 much more information than the fact or phenomenon 

 manifestly implies, and we cannot evolve that infor- 

 mation by means of study of the fact alone, however 

 intense that study may be. The correct explanation of a 

 fact and of the results of experiments bearing upon it, can 

 be given with safety only when a research is completed, 

 and its causes, conditions, and coincidences ascertained ; 

 -at the same time the whole course of an investigation is a 



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