58 BUREAU OP AMERICAN ETHNOLOGY [bull. 40 



language is at the present time, and there is no reason to presume 

 that it has ever been greater. Viewing the matter from this stand- 

 point, the hereditary mental differences of various groups of man- 

 kind, particularly within the same race, seem to be so slight that it 

 would be very difficult to believe that they account in any way for 

 the fundamental differences in the traits of distinct languages. 



Uncertainty of Definition of Linguistic Families 



The problem thus remains unsolved how to interpret the similari- 

 ties of distinct languages in cases where the similarities are no longer 

 sufficient to prove genetic relationship. From what has been said we 

 may conclude that, even in languages which can easily be proved to 

 be genetically related, independent elements may be found in vari- 

 ous divisions. Such independent elements may be due partly to new 

 tendencies which develop in one or the other of the dialects, or to 

 foreign influence. It is quite conceivable that such new tendencies 

 and foreign influences may attain such importance that the new 

 language may still, be considered as historically related to the ances- 

 tral family, but that its deviations, due to elements that are not found 

 in the ancestral language, have become so important that it can no 

 longer be considered as a branch of the older family. 



Thus it will be seen that the concept of a linguistic family can not 

 be sharply defined; that even among the dialects of one linguistic 

 family, more or less foreign material may be present, and that in this 

 sense the languages, as has been pointed out by PauV are not, in the 

 strict sense of the term, descendants of a single ancestral family. 



Thus the whole problem of the final classification of languages in 

 linguistic families that are without doubt related, seems destined to 

 remain open until our knowledge of the processes by which distinct 

 languages are developed shall have become much more thorough 

 than it is at the present time. Under these circumstances we must 

 confine ourselves to classifying American languages in those linguistic 

 families for wliich we can give a proof -of relationship that can not 

 possibly be challenged. Beyond this point we can do no more than 

 give certain definite classifications in which the traits common to 

 certain groups of languages are pointed out, while the decision as to 

 the significance of these common traits must be left to later times. 



1 Paul, Principien der Sprachgesehichte. 



