In 1967 the world of Milton studies was divided into two armed camps: one proclaiming (in the tradition of Blake and Shelley) that Milton was of the devil's party with or without knowing it, the other proclaiming (in the tradition of Addison and C. S. Lewis) that the poet's sympathies are obviously with God and the angels loyal to him.

The achievement of Stanley Fish's Surprised by Sin was to reconcile the two camps by subsuming their claims in a single overarching thesis: Paradise Lost is a poem about how its readers came to be the way they are - that is, fallen - and the poem's lesson is proven on a reader's impulse every time he or she finds a devilish action attractive or a godly action dismaying.

Fish's argument reshaped the face of Milton studies; thirty years later the issues raised in Surprised by Sin continue to set the agenda and drive debate.