SOURCE: "Appendix A," in Frankenstein or the Modern Prometheus: The 1818 Text, edited by James Rieger, The University of Chicago Press, 1982, pp. 222-29.

When a third edition of Frankenstein was produced in 1831, Shelley wrote a new introduction, reprinted below with James Rieger's notes. Shelley briefly recounts her biography, with an emphasis on her intellectual development and the events that led to the "waking dream" in which she first envisioned Victor Frankenstein and his creature.

The Publishers of the Standard Novels,¹ in selecting Frankenstein for one of their series, expressed a wish that I should furnish them with some account of the origin of the story. I am the more willing to comply, because I shall thus give a general answer to the question, so very frequently asked me—"How I, then a young girl, came to think of, and to dilate upon, so very hideous an idea?" It is...