SECT. IV.] UNITY OF MANKIND. 191 



kind, and in investigating their scope. In endeavouring to 

 render an impartial account of the inferences to which these 

 facts lead, we first observed a gradual mutability of the phy- 

 sical type, owing partly to external and partly to internal 

 agents. The degree and extent of this mutability, though by 

 no means slight, is nevertheless, in comparison with the great 

 differences existing between various races, not so strongly 

 marked as to decide the question, whether these differences 

 are to be considered as having specific value. We may, how- 

 ever, say, that the theory which assumes permanent specific 

 differences in mankind, appears to us less probable than the 

 opposite theory; and further, we venture positively to deny 

 the existence of permanency of type in the human form, it 

 being a phenomenon which could only arise from a long conti- 

 nued influence of climate, mode of life, external relations, and 

 defective mental culture, etc. 



There seems to exist this essential difference between man 

 and animals, that the mutability of his physical form has a 

 wider circle than that of the latter. It must not be objected 

 that man being, according to his organization, an animal, such 

 an assumption is gratuitous, inasmuch as the natural laws for 

 the development and changes of the animal economy must be 

 the same for both. It is in the first place undeniable that the 

 same human races can successively live in different climates, 

 and that the whole mode of life and external conditions to 

 which the same race may be subject, may be essentially altered, 

 not so those of animals ; and that the same race of men may 

 pass through various degrees of culture, which is not the case 

 with animals. If accordingly a wider sphere, with regard to all 

 these circumstances, is granted to man, it is not in contradic- 

 tion to the laws of nature that the limits of the mutability of 

 his nature are less confined than those of animals. Though 

 we could not entirely assent to the proofs for the unity of the 

 human race adduced by Blumenbach and Prichard derived 

 from analogy, namely, that the differences of human races are 

 less considerable than those found in animals which undoubtedly 

 belong to the same species ; still we agree with Prichard when 

 he says, that the external differences of men are not so great 



