CHAPTER IV. 



FALLACIES OF OBSERVATION. 



1. FROM the fallacies which are properly Prejudices, or 

 presumptions antecedent to, and superseding, proof, we pass 

 to those which lie in the incorrect performance of the proving 

 process. And as Proof, in its widest extent, embraces one or 

 more, or all, of three processes, Observation, Generalization, 

 and Deduction; we shall consider in their order the errors 

 capable of being committed in these three operations. And 

 first, of the first mentioned. 



A fallacy of misobservation may be either negative or 

 positive; either Non- observation or Mai- observation. It is 

 non-observation, when all the error consists in overlooking, or 

 neglecting, facts or particulars which ought to have been 

 observed. It is mal-observation, when something is not 

 simply unseen, but seen wrong ; when the fact or phenomenon, 

 instead of being recognised for what it is in reality, is mistaken 

 for something else. 



2. Non- observation may either take place by over- 

 looking instances, or by overlooking some of the circum- 

 stances of a given instance. If we were to conclude that a 

 fortune-teller was a true prophet, from not adverting to the 

 cases in which his predictions had been falsified by the event, 

 this would be non- observation of instances ; but if we over- 

 looked or remained ignorant of the fact that in cases where 

 the predictions had been fulfilled, he had been in collusion 

 with some one who had given him the information on which 

 they were grounded, this would be non -observation of cir- 

 cumstances. 



