On Genius. 385 
prize and the acuteness of his intellect will be 
just in proportion to the strength of his de- 
sires and aversions. Upon this theory then, 
it may be asked, wherein is the superiority 
of man over the brutes; some tribes of which 
possess the natural passions in equal, if not 
in greater force than the human race? I 
answer, in the power of associating and ge- 
neralizing his ideas, which man exercises to 
an almost boundless extent, but which the 
most sagacious brutes possess only within a 
very limited sphere.(h) 
On the strength, vividness, variety and 
extent of associations depends, as it seems 
to me, the’ great intellectual superiority of 
one man over another; and it may be shewn, 
I think, that the strength of our associations 
will be materially affected by the greater or 
less degree of susceptibility in our original 
constitution. It is very much the practice 
of philosophers, in the present day, to ex- 
plain the various operations of the mind by 
means of association. But, in most cases, 
this is only throwing the difficulty one step 
(h) Brutes cannot carry on a long train of general reasoning, because 
their associations embrace a comparatively small number of. ideas, and 
seldom extend far beyond the objects of direct bodily sensation. But 
within that narrow eircle, they often reason with very great acuteness, 
as the dog, for example, when lost, in searchipg for his master; and 
perhaps from this very circumstance, that their sensations are exceedingly 
keen and are concentrated on a very few objects, 
& C 
