494 LIABILITY TO ERROR. 



conception of its nature, and without, therefore, any effort 

 at self-extrication, or at remedy. They are perpetually 

 blundering without being conscious they are so doing ; they 

 are not led by experience to the correction of their mistakes. 

 Such animals are the subjects either of a congenital stupidity 

 of mental defect, or of disorder of the mental powers 

 subsequent to birth. 



On the other hand, just as there are individuals pecu- 

 liarly stupid in the detection and remedy of blunders, there 

 are others that are peculiarly clever, or intelligent. These 

 clever individuals display a singular freedom, from the com- 

 mission of mistakes, as well as a marked quickness in their 

 discovery, and ingenuity in their rectification, when com- 

 mitted. In other words, they seldom blunder, but when 

 they do so, they seldom fail speedily to detect and correct 

 their error. 



The recognition of man's errors may be supposed to imply 

 a higher degree of intelligence than the detection of their 

 own mistakes, or those of their fellows. Such recognition 

 includes a detection of various impostures or deceptions 

 practised on other animals by man : a subject more fully 

 alluded to in the chapters on * Deception' and ' Practical 

 Jokes.' ' Learned ' dogs, that play dominoes with him, ex- 

 press, by their gaze, their recognition of, and surprise at, 

 man's errors in the game, when he makes any (Watson). 



The causes of error in the lower animals may be either : 



1. Obvious ; or 



2. Discoverable only on close inquiry, or adequate re- 

 search ; or they 



3. Are not at present discoverable or demonstrable at 

 all. 



They may also be either real, or merely apparent : and 

 investigation may be necessary to discriminate between the 

 apparent and real. And further, they may be simple or 

 complex, and trivial or inadequate, disproportionate to the 

 result, or vice versa. 



The triviality of the causes of error is sometimes very 

 remarkable. This is illustrated by certain mistakes regard- 

 ing identity of person : as when a dog does not know its 



