384 On Genius. 
tion, Which man is called to exercise, exist- 
ing perhaps in the womb. It is the final 
motive of all his actions; it is the basis of all 
his associations; and exerts an influence on 
the most refined of his sentiments and the 
most excursive of his thoughts. Analogy 
renders it in the highest degree probable, 
that all our perceptions were accompanied 
originally by: a sense of pleasure and pain, 
and have become indifferent only by long- 
continued repetition, It is this capacity of 
discriminating the pleasurable from the pain- 
ful, which constitutes man a moral agent; 
which gives him an interest in the world 
which surrounds him, and forces him into 
action. 
Let us conceive, if it be possible, of a being 
capable of receiving impressions from ex- 
ternal objects, but destitute of all sensibility 
to pleasure and pain. Such a being, as he 
would want all intelligible motives of action, 
must continue inert and motionless, nor could 
answer one conceivable end of existence. 
Give him a sense of pleasure and pain, and 
you supply him at once with the springs of 
activity, and set his moral and intellectual 
machinery at work.—This is so completely 
the case, that, ceteris paribus, we may safely 
affirm, the ardour of his labours and enter- 
