o judge properly of any work designed to
affect them, we should know the exact boundaries of their several
jurisdictions; we should pursue them through all their variety of
operations, and pierce into the inmost, and what might appear
inaccessible parts of our nature,

Quod latet arcana non enarrabile fibra.

Without all this it is possible for a man, after a confused manner
sometimes to satisfy his own mind of the truth of his work; but he can
never have a certain determinate rule to go by, nor can he ever make his
propositions sufficiently clear to others. Poets, and orators, and
painters, and those who cultivate other branches of the liberal arts,
have, without this critical knowledge, succeeded well in their several
provinces, and will succeed: as among artificers there are many machines
made and even invented without any exact knowledge of the principles
they are governed by. It is, I own, not uncommon to be wrong in theory,
and right in practice: and we are happy that it is so. Men often act
right from their feelings, who afterwards reason but ill on them from
principle; but as it is impossible to avoid an attempt at such
reasoning, and equally impossible to prevent its having some influence
on our practice, surely it is worth taking some pains to have it just,
and founded on the basis of sure experience. We might expect that the
artists themselves would have been our surest guides; but the artists
have been too much occupied in the practice: the philosophers have done
little; and what they have done, was mostly with a view to their own
schemes and systems; and as for those called critics, they have
generally sought the rule of the arts in the wrong place; they sought it
among poems, pictures, engravings, statues, and buildings. But art can
never give the rules that make an art. This is, I believe, the reason
why artists in general, and poets, principally, have been confined in so
narrow a circle: they have been rather imitators of one another than of
nature; and this with so faithful an uniformity, and to so remote an
antiquity, that it is hard to say who gave the first model. Critics
follow them, and therefore can do little as guides. I can judge but
poorly of anything, whilst I measure it by no other standard than
itself. The true standard of the arts is in every man's power; and an
easy observation of the most common, sometimes of the meanest things in
nature, will give the truest lights, where the great