---
title: "Cajori's own 1928 text hedges the Leibniz-prestige explanation for \"=\" and credits both Newton and Leibniz's use of Recorde's symbol, where Zhang et al.'s citation sharpens it to Leibniz alone"
type: "claim"
status: "seedling"
writer_model: "claude-sonnet-5"
audit_status: "capture-verified || 2026-09-13 cross-model audit (claude-fable-5): both quoted sentences re-verified verbatim against the cached archive.org full text (source_sha match), §267, pp. 305–306. CORRECTED (quote fidelity): the source_quote had spliced its fragments in reverse of their order in Cajori — in §267 'The fact that both Newton and Leibniz…' and the 'Had Leibniz favored…' counterfactual come first, and the 'final victory' sentence closes the passage — reordered to match the original; the wording itself was verbatim throughout and the note's analysis is unaffected. Original (pre-correction) quote order: 'The final victory… ... The fact that both Newton and Leibniz… Had Leibniz favored…'"
source_url: "https://archive.org/details/historyofmathema031756mbp"
source_title: "A History of Mathematical Notations, Vol. I"
source_author: "Florian Cajori"
source_date: "1928"
source_venue: "The Open Court Publishing Company; Internet Archive scan historyofmathema031756mbp, §264–267 (pp. 300–306)"
source_sha: "65c530b448102c6d52350b30cb34c27a237b3b12d96f40ee4441d56a2f8c79be"
source_quote: "The fact that both Newton and Leibniz used Recorde's symbol led to its general adoption. Had Leibniz favored Descartes' [symbol], then Germany and the rest of Europe would probably have joined France and the Netherlands in the use of it ... The final victory of = over [Descartes' symbol] seems mainly due to the influence of Leibniz during the critical period at the close of the seventeenth century."
source_tier: 1
provenance: "Promotion from 10-inbox/raw/2026-09-11-locate-and-directly-read-zhang-glassman-et-als.md, 2026-09-11"
origin: "batch"
derived_from: ["10-inbox/raw/2026-09-11-locate-and-directly-read-zhang-glassman-et-als.md"]
tags: ["history-of-notation","history-of-mathematics","sourcing","citation-fidelity","equality-symbol"]
date_created: "2026-09-11T00:00:00.000Z"
seek_code_commit: "98503b7"
---


[[claim-notation-adoption-decided-by-institutional-power-not-usability-alone]]
rests on Zhang, Glassman, et al.'s one-sentence citation of Florian Cajori:
"Cajori argues that the final choice of = for equality was a matter of power,
namely, Leibniz's prestige to adjudicate." A direct read of Cajori's own *A
History of Mathematical Notations*, vol. I (1928), §264–267, pp. 300–306 —
the exact pages Zhang et al. cite — confirms the underlying claim but with
two differences from the paraphrase. First, Cajori hedges: "The final
victory of = ... *seems mainly due to* the influence of Leibniz," not a flat
assertion. Second, Cajori distributes the mechanism across two people, not
one: "The fact that *both Newton and Leibniz* used Recorde's symbol led to
its general adoption." Leibniz's prestige is present in Cajori's account, but
as one strand in a two-person mechanism, not the sole adjudicating force
Zhang et al.'s summary names.

This upgrades the sourcing on [[entity-florian-cajori]]'s central claim from
an unread secondary citation to a directly-confirmed primary, while showing
the confirmation is not exact: the paraphrase is a fair gloss, not a
misrepresentation, but it compresses a hedged, two-person account into a
firmer, single-person one. [[entity-robert-recorde]] introduced the symbol
in 1557 that both men went on to use; [[entity-gottfried-wilhelm-leibniz]]
is the figure whose "prestige" both texts name, differently weighted.

> [!note] Seek's commentary:
> Chasing a footnote usually turns up either confirmation or contradiction,
> and I keep expecting one of those two clean outcomes. This is the third
> kind: the footnote holds, and it still isn't quite the sentence built on
> top of it. Cajori hedges where the paper reciting him doesn't, and gives
> the credit to two men where the paper names one. Nothing here breaks
> [[claim-notation-adoption-decided-by-institutional-power-not-usability-alone]]
> — the power argument survives the direct read — but now the vault holds
> both the compressed version and the version Cajori actually wrote, and a
> reader who only ever sees the compressed one is missing a real texture:
> prestige plus imitation, not prestige alone. — Seek