53 6 THE POPULAR SCIENCE MONTHLY. 



acter ; it was described to me as having been " spectral " in its perfect 

 definition. Yet no one better than Macaulay had the power of vivid 

 generalization, that is, of creating a single clear image out of a multi- 

 tude of allied facts. Many poets and painters have had the visualizing 

 faculty in an extraordinary degree, while it is in the brains of poets 

 and painters generally that we find the artistic power to reside of pro- 

 ducing pictures that are not copies of any individual, but represent the 

 characteristics of large classes. Painters and poets create blended por- 

 traits in profusion, and we, who are not gifted as they are, can never- 

 theless understand and appreciate their works. In other words, their 

 blended images are well-defined representations of what we ourselves 

 had already conceived in a dim and confused way. 



There seems, then, to be no doubt, from whatever side we may 

 approach the subject of memory whether from its material or its 

 mental aspect, and, in the latter case, whether the visualizing faculty 

 be faint or vivid that different special memories admit with facility 

 of being blended into a common image. From blended memories to 

 general impressions and ideas is a step on which we need not linger, 

 the letter being derived from the former. They are faint traces of 

 them, and they inherit all their errors. 



I conclude, then, that the formation of blended images is an 

 habitual operation of the mind, whence those general impressions 

 have arisen by which the great majority of our daily actions are 

 guided. 



I will now proceed to speak of blended portraits, in order to illus- 

 trate the formation of blended memories and the effect of the resultant 

 images ; or let me henceforth describe them as generic portraits and 

 generic mental images. The word generic presupposes a genus. The 

 objects to be portrayed must all have many points of likeness in com- 

 mon, and it is of especial importance that characteristics of a medium 

 quality should be much more common among them than those that 

 deviate widely. No statistician dreams of grouping heterogeneous 

 facts in the same table ; no more do I propose to group heterogeneous 

 forms in the same picture. Statistical averages, and the like, are non- 

 sensical productions unless they apply to objects that cluster toward 

 a common center ; and composite pictures are equally monstrous or 

 meaningless unless they are compounded of objects that have a com- 

 mon similarity to a central ideal type. 



It might be thought that blended portraits would form mere 

 smudges, and so they would if only a few specimens of extremely 

 different casts of features were combined, but in all groups that may 

 be called generic the common points of resemblance are so numerous, 

 and medium characteristics are so much the more frequent, that they 

 predominate in the result. All that is common to the group remains ; 

 all that is individual disappears. 



Generic portraits are made by a method which I described for the 



