No character in Paradise Lost has generated more disagreement than its Satan, who dominates the poem's opening books with speeches of defiant grandeur before Milton's narrative gradually strips him down to a physically diminished, increasingly pathetic figure by the poem's later books. The gap between Satan's early rhetorical power, declaring it "better to reign in Hell, than serve in Heaven," and his eventual degradation is the whole of the critical argument in miniature.
By the Romantic era, poets including William Blake and Percy Bysshe Shelley had begun reading Satan as the poem's real hero, a rebel against arbitrary authority whose energy Milton's own sympathies betrayed even as his stated theology condemned him. Blake's often quoted remark, that Milton wrote of Satan and Hell "at liberty" and of God and Heaven "in fetters" because he was "a true poet and of the Devil's party without knowing it," became the anchor of what later critics called the Satanist or Romantic reading.
C. S. Lewis's 1942 study A Preface to Paradise Lost mounted the fullest scholarly counterargument, insisting the poem is a deliberate epic in the classical mold and that Milton's own theology, an orthodox seventeenth century Christian's view of pride as the root sin, condemns Satan consistently from the first line to the last: any reader's early attraction to him is the poem doing exactly what a portrait of temptation is supposed to do. Neither reading has fully displaced the other, and the disagreement remains a standard entry point into how Milton scholarship as a whole is taught.