MAN AND BRUTE. 5 



admit of gradual development from a zero level. This I posit 

 as the second consideration. 



Again, so long as it is passing through the lower phases 

 of its development, the human mind assuredly ascends through 

 a scale of mental faculties which are parallel with those that 

 are permanently presented by the psychological species of the 

 animal kingdom. A glance at the Diagram which I have 

 placed at the beginning of my previous work will serve to 

 show in how strikingly quantitative, as well as qualitative, a 

 manner the development of an individual human mind 

 follows the order of mental evolution in the animal kingdom. 

 And when we remember that, at all events up to the level 

 where this parallel ends, the diagram in question is not an 

 expression of any psychological theory, but of well-observed 

 and undeniable psychological fact, I think every reasonable 

 man must allow that, whatever the explanation of this 

 remarkable coincidence may be, it certainly must admit of 

 some explanation — i.e. cannot be ascribed to mere chance. 

 But, if so, the only explanation available is that which is 

 furnished by the theory of descent. These facts, which I 

 present as a third consideration, tend still further — and, 

 I think, most strongly — to increase the force of antecedent 

 presumption against any hypothesis which supposes that the 

 process of evolution can have been discontinuous in the region 

 of mind. 



Lastly, it is likewise a matter of observation, as I shall 

 fully show in the next instalment of this work, that in the 

 history of our race — as recorded in documents, traditions, 

 antiquarian remains, and flint implements — the intelligence of 

 the race has been subject to a steady process of gradual 

 development. The force of this consideration lies in its 

 proving, that if the process of mental evolution was suspended 

 between the anthropoid apes and primitive man, it was again 

 resumed with primitive man, and has since continued as un- 

 interruptedly in the human species as it previously did in the 

 animal species. Now, upon the face of these facts, or from 

 a merely antecedent point of view, such appears to me, to say 



