Q14 PHILOSOPHY OF ZOOLOGY. 
are qualified to communicate to the mind. It now remains 
that we attend to the sensations themselves, in reference to 
the processes performed upon them by the mind, with the 
view of becoming acquainted with the faculties of that mys- 
terious part of our nature. 
In conducting this inquiry, it is difficult to avoid the 
use of ambiguous phrases; for almost every term which 
can be applied to mind, has been loaded with a variety of 
significations. It will be our aim to render obvious the 
meaning of the terms here employed, by the descriptions 
which accompany them. 
When we attend to the phenomena displayed by the 
mind, we perceive that it exhibits certain relations to the 
sensations of the body, changes resulting from their produc- 
tion, and consequent efforts cf volition. 
These different states or conditions of the mind have been 
observed to beregulated by peculiar laws, and tobesubservient 
to particular purposes in the animal economy. ‘They have 
had bestowed on them specific appellations, to express their 
characters ; and they have generally been denominated the 
Attributes, Faculties, or (in consequence of volition produ- 
cing change) Powers of the Mind. Trivial objections have 
been urged against the use of these terms, as implying that 
the mind is composed of different parts ; and, consequent ys 
not entitled to its prerogative of unity. Of the essence of 
mind we absolutely know nothing ; and hence the various 
phrases, Unity, Indivisibility, Immateriality, and others, 
which have been employed to express the nature of this es- 
sence, are, in fact, expressions of our own ignorance and pre- 
sumption. When we witness the mind capable of exciting 
action in matter, and of being excited to action by matter,— 
exhibiting its identity by its local residence,—variable in 
its relations to matter,—variable relatively to its own con- 
ditions,—capable of exercising different functions at the 
