urer than another,
except as more or less compounded, whereas there is certainly a sense of
purity or impurity in the most compound and neutral colors, as well as
in the simplest, a quality difficult to define, and which the reader
will probably be surprised by my calling the type of energy, with which
it has certainly little traceable connection in the mind.

Sec. 3. Originally derived from conditions of matter.

Sec. 4. Associated ideas adding to the power of the impression. Influence
of clearness.

Sec. 5. Perfect beauty of surface, in what consisting.

I believe however if we carefully analyze the nature of our ideas of
impurity in general, we shall find them refer especially to conditions
of matter in which its various elements are placed in a relation
incapable of healthy or proper operation; and most distinctly to
conditions in which the negation of vital or energetic action is most
evident, as in corruption and decay of all kinds, wherein particles
which once, by their operation on each other, produced a living and
energetic whole, are reduced to a condition of perfect passiveness, in
which they are seized upon and appropriated, one by one, piecemeal, by
whatever has need of them, without any power of resistance or energy of
their own. And thus there is a peculiar painfulness attached to any
associations of inorganic with organic matter, such as appear to involve
the inactivity and feebleness of the latter, so that things which are
not felt to be foul in their own nature, yet become so in association
with things of greater inherent energy; as dust or earth, which in a
mass excites no painful sensation, excites a most disagreeable one when
strewing or staining an animal's skin, because it implies a decline and
deadening of the vital and healthy power of the skin. But all reasoning
about this impression is rendered difficult, by the host of associated
ideas connected with it; for the ocular sense of impurity connected with
corruption is infinitely enhanced by the offending of other senses and
by the grief and horror of it in its own nature, as the special
punishment and evidence of sin, and on the other hand, the ocular
delight in purity is mingled, as I before observed, with the love of the
mere element of light, as a type of wisdom and of truth; whence it seems
to me that we admire the transparency of bodies, though probably it is
still rather owing to our sense of more perfect order and arrangement