their effect to a similar exhibition of properties quite foreign to the imagination; insomuch that in every line of the most applauded poems, we meet with either ideas drawn from the external senses, or truths discover'd to the understanding, or illustrations of contrivance and final causes, or above all the rest, with circumstances proper to awaken and engage the passions. It was therefore necessary to enumerate and exemplify these different species of pleasure; especially that from the passions, which as it is supreme in the noblest works of human genius, so being in some particulars not a little surprising, gave an opportunity to inliven the didactic turn of the poem, by introducing a piece of machinery to account for the appearance.
After these parts of the subject which hold chiefly of admiration, or naturally warm and interest the mind, a pleasure of a very different nature, that from ridicule came next to be consider'd. As this is the foundation of the comic manner in all the arts, and has been but very imperfectly treated by moral writers, it was thought proper to give it a particular illustration, and to distinguish the general sources from which the ridicule of characters is deriv'd. Here too a change of stile became necessary; such a one as might yet be consistent, if possible, with the general taste of composition in the serious parts of the subject: nor is it an easy task to give any tolerable force to images of this kind, without running either into the gigantic expressions of the mock-heroic, or the familiar and pointed raillery of profess'd satyr; neither of which would have been proper here.
