CH. XXI.] GENESIS OF MAN, INTELLECTUALLY. 317 



in capacity is but eleven cubic inches ! That is to say, the 

 difference in volume of brain between the highest and the 

 lowest man is at least six times as great as the difference 

 between the lowest man and the highest ape. And if we 

 were to take into the account the differences in structural 

 complexity, as indicated by the creasing and fu'"rowing 

 of the brain-surface, we should obtain a yet more astonishing 

 contrast. Yet, powerfully as this anatomical fact confirms 

 the position we have all along been upholding, its full value 

 will not be apparent if we are so dazzled by it as to overlook 

 the significance of the lesser difference between the gorilla 

 and the aboriginal inhabitant of India. As the Duke of Argyll 

 very properly observes, we do right in setting a higher 

 value in classification upon the eleven inches which intervene 

 between the goriJla and the Hindu than upon the sixty-eight 

 inches which intervene between the Hindu and the English- 

 man. For " the significance set by the facts of nature upon that 

 difference of eleven cubic inches .... is the difference between 

 an irrational brute confined to some one climate and to some 

 limited area of the globe, — which no outward conditions can 

 modify or improve, — and a being equally adapted to the 

 whole habitable world, with powers, however undeveloped, of 

 comparison, of reflection, of judgment, of reason, with a sense 

 of right and wrong, and with all these capable of accumu- 

 lated acquisition, and therefore of indefinite advance." 

 Though somewhat exaggerated in what it denies to the 

 brute, and much more in what it claims for the aboriginal 

 man, this statement contains a kernel of truth which is of 

 value for our present purpose, and which is further illustrated 

 by the fact that a minimum of brain-substance "is constantly 

 and uniformly associated with all the other anatomical 

 peculiarities of man. Below that minimum the whole 

 accompanying structure undergoes far more than a corre- 

 sponding change, — even the whole change between the lowest 

 Bavage and the highest ape. Above that minimum, all 



