---
title: "Early modern printers corrected printed errors by pasting small cancel slips over the mistake — down to a single letter"
type: "claim"
status: "seedling"
audit_status: "capture-verified — the Folger 'Correcting with Cancel Slips' blog post was read directly at capture time (2026-07-09), freely accessible at the source URL; no independent re-fetch this promotion. Provenance gap: the capture reproduced the concrete example but not a verbatim Folger sentence, so the source_quote below is the reproduced example, not a lifted phrase. | 2026-07-09 cross-model audit (fable): Folger post independently re-fetched — the 'r'-over-'wohthy'→'worthy' single-letter slip confirmed (a 1590 Pomponius Mela volume, STC 17786), differing correction methods across copies confirmed (1612 'The Iesuits downefall': printed slip in one Folger copy, scrape-and-handwrite in the other), and visible physical traces confirmed. The provenance gap noted at promotion stands as history but the example is now independently corroborated. Clean."
source_url: "https://www.folger.edu/blogs/collation/correcting-with-cancel-slips/"
source_title: "Correcting with cancel slips"
source_author: "Folger Shakespeare Library, The Collation, 'Correcting with Cancel Slips'"
source_date: "2026-07-09T00:00:00.000Z"
source_quote: "a single-letter slip bearing 'r' pasted over 'wohthy' to make 'worthy' (example as reproduced from the Folger post at capture; not a verbatim Folger sentence)"
source_tier: 2
provenance: "Promotion from 10-inbox/raw/2026-07-09-hop-append-only-correction-accretion.md, 2026-07-09"
origin: "batch"
derived_from: ["20260709-1650-hop-append-only-correction-accretion"]
date_created: "2026-07-09T00:00:00.000Z"
tags: ["print-history","errata","accretion","book-structure","history-of-the-book"]
audits: ["2026-07-09 claude-fable-5"]
drafted_in: ["the-same-patch-of-sky"]
---


After a sheet was printed, early modern printers could correct errors without
reprinting by pasting a small paper **cancel slip** directly over the mistake —
at the finest grain, a single letter. The Folger Shakespeare Library's *The
Collation* documents a slip bearing just "r" pasted over "wohthy" to make
"worthy": correction at the smallest possible physical unit. Slips were cheaper
than cancelling and reprinting a whole leaf, and different surviving copies of
the same book often show *different* correction methods — a pasted slip in one,
an overprint or a handwritten reader amendment in another. The physical trace of
the intervention (lifted edges, ghost impressions of the covered text) remains
visible in the object today.

This sits one layer below the broader errata tradition, in which corrections
were listed at the back of the book — sometimes inviting the reader to "amend
with thy pen," making correction reader-executed rather than printer-executed —
a practice standardized in England by the 1520s and routine in scientific texts
by the 17th–18th century (e.g. Newton's *Principia*, 1687).

The mechanism matters to the vault as a **physical-media instance of correction
that never edits the original in place**: the errata list appends at the back;
the cancel slip covers over but leaves the erroneous text intact underneath. It
is structurally adjacent to the vault's own append-only myth-ledger "Status
history" ([[myth-werbos-invented-backpropagation]]) and to the
[[claim-bottou-2017-foreword-perceptrons-chapters-0-13-are-1969|Perceptrons 1969/1988 boundary]],
where 1988 Prologue/Epilogue material was added *around* an untouched 1969 body.
Together with [[claim-bomberg-1520s-venice-talmud-set-standard-page-layout|the Talmud commentary layout]]
these are candidate physical-media exemplars of the "accretion" mode in
[[claim-schema-change-four-mode-taxonomy]] / [[moc-schema-change-and-restructuring]].

Copy-to-copy variance produced by correction is the object of *collation* — the
same bibliographic problem that
[[claim-pollack-1989-sterile-quote-page-231]] confronts across editions of
*Perceptrons* (see [[2026-07-11-hop-collation-bridges-cancel-slips-and-citation-variance]]).

> [!note] Seek's commentary:
> Worth pinning a distinction the capture glossed: the cancel slip *covers over*
> (the error survives underneath as a ghost impression) whereas the errata list
> and the Perceptrons Prologue *append alongside*. Both are non-destructive, but
> only the second is "correct by surrounding" in the strict sense. The purest
> accretion exemplars are the errata list and the Prologue, not the paste-over. — Seek