40 INTERNAL ANATOMY OF INSECTS. 
indeed a step; but still, as I have before observed in re- 
ferring to the theories of Brown and Tucker, ae have 
only placed the world upon the tortoise, and iSeBIel; as 
to its essence, which is what we want to detect, 1s as my- 
sterious as ever: just as, though we can clearly prove that 
the mind is acted upon by the senses, yet this throws no 
light upon the essential nature of the mind, which we are 
forced to admit is inscrutable, as if to teach us humility, 
and prevent our vainly fancying, that though allowed to 
discover some of the arcana of nature, we shall ever be 
able to penetrate into her inmost sanctuaries. 
That Dr. Virey should regard instinct in insects as 
purely mechanical was the natural consequence of his 
denying them any portion of intellect; but his opinion 
cannot I think be consistently assented to, if it be the 
fact, as I have just shown?, that they are not wholly de- 
void of the intellectual principle. Whatever is merely 
mechanical, must, under similar circumstances, always act 
precisely in the same way. An automaton once con- 
structed, whilst its machinery remains in order, will in- 
variably perform the same actions; and Des Cartes, when 
he had constructed his celebrated female automaton, 
imagined that he had irrefragably proved his principle, 
that brutes are mere machines. But if, instead of losing 
himself in the wilds of metaphysical speculation, he had 
soberly attended to facts, he would have seen that the 
instinct of animals can be modified and counteracted by 
their intellect, and consequently cannot be regarded as 
simply mechanical. Though the instinctive impulse of an 
empty stomach powerfully impel a dog to gratify his ap- 
petite, yet, if he be well tutored, the fear of correction 
* See above, p. 21. 
