ombining or
classifying them, as well might a preacher expect in one sermon to
express and explain every divine truth which can be gathered out of
God's revelation, as a painter expect in one composition to express and
illustrate every lesson which can be received from God's creation. Both
are commentators on infinity, and the duty of both is to take for each
discourse one essential truth, seeking particularly and insisting
especially on those which are less palpable to ordinary observation, and
more likely to escape an indolent research; and to impress that, and
that alone, upon those whom they address, with every illustration that
can be furnished by their knowledge, and every adornment attainable by
their power. And the real truthfulness of the painter is in proportion
to the number and variety of the facts he has so illustrated; those
facts being always, as above observed, the realization, not the
violation of a general principle. The quantity of truth is in proportion
to the number of such facts, and its value and instructiveness in
proportion to their rarity. All really great pictures, therefore,
exhibit the general habits of nature, manifested in some peculiar, rare,
and beautiful way.

CHAPTER V.

OF THE RELATIVE IMPORTANCE OF TRUTHS:--THIRDLY, THAT TRUTHS OF
COLOR ARE THE LEAST IMPORTANT OF ALL TRUTHS.

Sec. 1. Difference between primary and secondary qualities in bodies.

In the two last chapters, we have pointed out general tests of the
importance of all truths, which will be sufficient at once to
distinguish certain classes of properties in bodies, as more necessary
to be told than others, because more characteristic, either of the
particular thing to be represented, or of the principles of nature.

According to Locke, Book ii. chap. 8, there are three sorts of qualities
in bodies: first, the "bulk, figure, number, situation, and motion or
rest of their solid parts: those that are in them, whether we perceive
them or not." These he calls primary qualities. Secondly, "the power
that is in any body to operate after a peculiar manner on any of our
senses," (sensible qualities.) And thirdly, "the power that is in any
body to make such a change in another body as that it shall operate on
our senses differently from what it did before: these last being usually
called _powers_."

Sec. 2. The first are fully characteristic, the second imperfe