MAN, PHYSICALLY CONSIDERED. 469 



' Though this reasoning will not fully explain all the va- 

 rieties of human appearance, yet it is undoubtedly in gen- 

 eral is correct. These causes are almost infinitely va- 

 ried and combined, and consequently we find in every 

 nation, village, and even family, striking diversities of 

 complexion, form, and stature.' 



Although, however, it may be admitted that all the 

 races of men are of one family, it does not by any means 

 follow that they are all intellectually equal. Many per- 

 sons seeing, as they suppose, sufficient evidence of the 

 inferiority in intellectual or physical power, of some of 

 the races of men, have concluded that this is in itself a 

 sufficient argument to disprove identity of origin. But a 

 moment's reflection will show us that we are not compel- 

 led to maintain the intellectual equality of the different 

 portions of the human family, simply because we hold 

 that they descended from one pair. In the course of 

 ages, the various collateral branches of the same stock 

 may diverge from each other untifr in many traits 

 both physical and intellectual, they become widely dif- 

 ferent, and the peculiarities thus acquired become per- 

 manent, at least to such a degree as to require an 

 equally long series of causes and effects to restore the 

 original character. 



It is so with other animals. The dog, for instance, is 

 universally admitted to form one species, yet how great 

 the variety of breeds produced by the influence of cli- 

 mate, and other circumstances. One breed is perma- 

 nently and unchangeably acute in the sense of smell, 

 another is noted for speed of foot. One is sagacious 

 another strong, and a third ferocious. We say these 

 peculiarities are permanent and unchangeable and they 

 are so, at least to such a degree that it would require a 

 very long course of years, and very special training, the 

 results of which should accumulate through many gen- 

 erations, to reverse them. 



Now it may be so with men. We do not mean to 

 discuss here the question of the equality of the negro, or 

 any other race to the rest of mankind in intellectual 

 power. We only say that their present equality does not 

 necessarily follotc from their common origin. The lapse 



