Which of these is a short quotation at the front of a book intended to suggest its theme?

In literature, an epigraph is a phrase, quotation, or poem that is set at the beginning of a document or component. The epigraph may serve as a preface, as a summary, as a counter-example, or to link the work to a wider literary canon, either to invite comparison or to enlist a conventional context.

The long quotation from Dante's Inferno that prefaces T. S. Eliot's "The Love Song of J. Alfred Prufrock" is part of a speech by one of the damned in Dante's Hell. Linking it to the monologue which forms Eliot's poem adds a comment and a dimension to Prufrock's confession. The epigraph to Eliot's Gerontion is a quotation from Shakespeare's Measure for Measure. Eliot's "The Hollow Men" uses the line "Mistah Kurtz, he dead" from Joseph Conrad's Heart of Darkness as one of its two epigraphs.