From A Defence of Poetry
The distorted notions of invisible things which Dante and his rival
Milton have idealized are merely the mask and the mantle in which these
great poets walk through eternity enveloped and disguised. It is a
difficult question to determine how far they were conscious of the
distinction which must have subsisted in their minds between their own
creeds and that of the people. Dante at least appears to wish to mark the
full extent of it by placing Riphæus, whom Virgil calls
justissimus unus, in Paradise, and observing a most heretical
caprice in his distribution of rewards and punishments. And Milton's poem
contains within itself a philosophical refutation of that system of
which, by a strange and natural antithesis, it has been a chief popular
support. Nothing can exceed the energy and magnificence of the character
of Satan as expressed in Paradise Lost. It is a mistake to suppose that
he could ever have been intended for the popular personification of
evil. Implacable hate, patient cunning, and a sleepless refinement of
device to inflict the extremest anguish on an enemy, these things are
evil; and although venial in a slave are not to be forgiven in a tyrant;
although redeemed by much that ennobles his defeat in one subdued, are
marked by all that dishonours his conquest in the victor. Milton's Devil
as a moral being is as far superior to his God as one who perseveres in
some purpose which he has conceived to be excellent in spite of adversity
and torture, is to one who in the cold security of undoubted triumph
inflicts the most horrible revenge upon his enemy, not from any mistaken
notion of inducing him to repent of a perseverance in enmity, but with
the alleged design of exasperating him to deserve new torments. Milton
has so far violated the popular creed (if this shall be judged a
violation) as to have alleged no superiority of moral virtue to his God
over his Devil. And this bold neglect of a direct moral purpose is the
most decisive proof of Milton's genius. He mingled as it were the
elements of human nature, as colours upon a single pallet, and arranged
them into the composition of his great picture according to the laws of
epic truth; that is, according to the laws of that principle by which a
series of actions of the external universe and of intelligent and ethical
beings is calculated to excite the sympathy of succeeding generations of
mankind.
(Earlier in his "Defence of Poetry," it
should be stressed, Shelley complicates this notion of the author's
refusal to adopt a moral purpose as he underscores the essentially
ethical nature of all literary discourse.)