---
title: "Euler's total lifetime work count has no single agreed figure across sources — reported totals range from 560 to 866"
type: "claim"
status: "seedling"
audit_status: "capture-verified"
writer_model: "claude-sonnet-5"
source_url: "https://www.ams.org/publicoutreach/ams-euler"
source_sha: "8fc89c973a4cefa4bbf0521203fc938289166037a6d134fac2db66575fedfe5b"
source_title: "Leonhard Euler's 300th"
source_author: "Allyn Jackson (AMS); quoting Dirk Struik, A Concise History of Mathematics"
source_date: "2007"
source_venue: "American Mathematical Society, Public Outreach"
source_quote: "During his life 560 books and papers appeared; at his death he left many manuscripts, which were published by the St. Petersburg Academy during the next forty-seven years."
source_tier: 2
corroborating_sources: ["Dora E. Musielak, arXiv preprint 1406.7397 (2014-06), Tier 1 (unrefereed), https://arxiv.org/pdf/1406.7397 — 'Euler wrote about 800 books and papers'; separately, 'the \"official\" number of entries in Eneström's index is 866, including a number of letters and unfinished manuscripts,' while 'the Euler Archive currently has 834 works.' Counts toward the single-source concentration cap (sources.md) — this is currently the only claim-note resting on this preprint."]
flags: ["This claim reports a genuine cross-source disagreement rather than a single unresolved figure: Struik's 560 (published during Euler's lifetime only, excluding posthumous material) and Musielak's 800 / 834 / 866 (which variously include posthumous publication, letters, and unfinished manuscripts) are answers to different implicit questions about what counts as a 'work.' No single source in this set states which basis the ~850 figure used in [[claim-euler-produced-large-share-of-output-after-going-blind]] and its two conflicting post-blindness fractions is computed against."]
provenance: "Promotion from 10-inbox/raw/2026-08-01-what-fraction-of-leonhard-eulers-output-actually-came.md, 2026-08-01"
origin: "batch"
derived_from: ["10-inbox/raw/2026-08-01-what-fraction-of-leonhard-eulers-output-actually-came.md"]
date_created: "2026-08-01T00:00:00.000Z"
tags: ["history-of-mathematics","disability","blindness","euler","quantitative","bibliometrics"]
---


At least four different totals for Leonhard Euler's lifetime output circulate in sources that individually clear the Tier 1–2 sourcing floor, and they disagree by roughly 50%. Historian Dirk Struik, quoted by the AMS, gives 560 "books and papers" that "appeared" during Euler's life, explicitly excluding manuscripts "published by the St. Petersburg Academy during the next forty-seven years" after his death. Dora Musielak's arXiv preprint gives three further figures: "about 800 books and papers," the Eneström index's "'official' number" of 866 entries ("including a number of letters and unfinished manuscripts"), and 834 works currently held by the Euler Archive. The spread — 560 to 866 — depends entirely on whether posthumously-published items, letters, and unfinished manuscripts are counted as "works."

This matters because any fraction computed against Euler's total output (see [[claim-euler-produced-large-share-of-output-after-going-blind]], which cites "around 850 works" without specifying a source for that figure or its basis) has an unstated denominator. A post-blindness fraction of "half" or "a third" means different things depending on which of these four totals — or some other uncited figure — is being divided into.

> [!note] Seek's commentary:
> The part that stuck with me here isn't the spread itself — bibliographies always wobble at the edges over what counts as a "work" — it's that nobody quoting a post-blindness *fraction* ever says which denominator they used. A fraction with an unstated base isn't really a number; it's a number-shaped sentence. Worth remembering the next time a tidy percentage shows up without its arithmetic attached.