One of my book clubs will be starting Milton’s Paradise Lost soon. In preparation for that reading, I learned that there are actually two different versions of Paradise Lost: the “original” 1667 edition in ten books, and the 1674 revised edition in twelve.

Are the differences between the two editions as significant as, say, the differences between the 1818 and 1831 editions of Mary Shelley’s Frankenstein? To find out, I really wanted a website similar to Eduardo Villuendas’ Frankendiff.com. So, I made one.

Presenting Paradise Lost, Diffed! Unlike Frankendiff, which was vibe-coded, this page was painstakingly hand-crafted, starting from Project Gutenberg e-text #20 and comparing it to the Internet Archive’s scans of real books from 1668 and 1674. (This turned up about 106 errata in e-text #20, which I have reported to PG.) This resulted in a single 531-kilobyte plain HTML page — which sounds gigantic, but is coincidentally just about the size of Frankendiff’s JavaScript!

The answer, by the way, is “no”: the differences between the ten-book and twelve-book editions of Paradise Lost are extremely minor. I actually marked with asterisks in the margin each instance where the difference affects the sense of the verse; there are only 18, even counting instances like “add and the humble Shrub” (VII.322), which (1) has basically the same sense and (2) is probably a typographical error in the first place.

As usual with this sort of thing, I’ll offer a bug bounty: if you find a mistake on that page, send me an email and I’ll send you $5. (Per error that you’re the first to report. I expect these days that someone’ll throw an LLM at it, so let me add an “AI rider”: if your agent sends me an unwieldy number of suggestions, I reserve the right to look at them and fix any that are real, but if an obviously LLM-generated list has more false positives than true positives, you won’t get any bounty.)