SCIENTIFIC STUDY OF HUMAN TESTIMONY. 63 



objective words and phrases and thoughts of his own brain, which, per- 

 haps, have long been parts of his mental possessions, rise up like ghosts 

 in the midst of his narration, throw aside the original words and phrases 

 and thoughts, and take tbeir places so perfectly and so harmoniously 

 that the intrusion is not suspected. 



It may be said indeed, it is often said that memory is a distinct 

 and narrow faculty, in no way correlated to other and more important 

 faculties, and that its perfectness or imperfectness has little relation to 

 the cerebral force. Even if this view of the nature of memory were the 

 correct one, it would not invalidate what is here claimed of the relation 

 of memory to human testimony. But this theory of the nature and office 

 of memory is not the correct one ; it is opposed to all that is known of 

 the brain and of its functions, whether studied physiologically or psy- 

 chologically. Memory is simply a register of a small fraction of the 

 impressions made on the brain ; there are, therefore, as many different 

 kinds of memory as there are different faculties or combinations of facul- 

 ties. Memory is a measure of mind ; but, as there are as many varieties 

 of memory as there are varieties of talents in man, the memory of any 

 man can only measure the talent peculiar to himself. We remember 

 what we have a capacity to comprehend. Any man, it has been said, 

 is willing to admit that his memory is poor, but no one will admit that 

 his judgment is poor ; and yet judgment is largely the result of mem- 

 ory. One may have a good judgment in some departments, but a very 

 poor judgment in other departments ; but, in those departments in 

 which the judgment is good, the memory must also be good. 



The relation of memory to mind is illustrated, if not demonstrated, 

 in the early and late history of infant prodigies, such as blind Tom 

 the musician, Colburn the mathematician, and the famous " boy ora- 

 tor." An analysis of the mental powers of any of these prodigies 

 brings out these four facts common to them all : 1. Extraordinary mem- 

 ory in some one department ; 2. Correspondingly extraordinary genius 

 in that department ; 3. Marked and unusual deficiency of other mental 

 qualities, amounting in some instances to idiocy ; 4. Decline of their 

 special gifts corresponding to the development of other faculties on 

 reaching maturity. " In monstrosities Nature reveals her secrets ; " the 

 physiology of mind, the general relation of mind to brain, and the rela- 

 tion of memory to mind, can all be studied effectively through infant 

 prodigies. In no class of beings are the limitations of the human brain 

 so thoroughly demonstrated as in these very prodigies that are supposed 

 to illustrate in a marvelous way the capacities of intellect : all their 

 special endowments are bestowed at the price of general endow- 

 ments ; the ordinary io sacrificed to the extraordinary. If they ever 

 mature and become well-balanced citizens, the particular genius that 

 made their childhood famous must correspondingly suffer. Even the 

 average child, as we have seen, loses its memory in certain directions 

 as it advances to maturity; hence the common but erroneous belief 



