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Eratosthenes

Eratosthenes

0

Near balanceFormula-derived score

Alexandrian librarian whose circumference, Geography, chronology, obliquity, and later-attributed sieve reach the public through Cleomedes, Strabo, MacTutor, and Britannica. Documented harms: no autograph, later attribution, classroom reconstructions refused as acts. He did not typeset Jones.

Alexandrian royal-library scholarship as later reportedgeodetic and cartographic measurement as quoted by Strabo and Cleomedeslater-attributed arithmetic not treated as a recovered autograph

Impact

Not rated yet: the verified records linked to this person, without a numeric impact.

Editorial assessment (context, not the score)

The page is not a classroom globe and not a unique author of later Ptolemy. The documented public file in English is later: a received librarianship, a circumference method reported by Cleomedes, a Geography and chart quoted by Strabo, chronological tables, an obliquity heading, and a sieve later attributed. Those are knowledge paths of medium-to-high confidence on the later reports, not autographs. There is no honest dozen of welfare harms to manufacture from a missing Mouseion diary. He did not typeset Perseus. Editors and geographers did that work. Confidence is high that the later pages exist, low on unique stadion conversions. Later Strabo and MacTutor pages remain the dated record.

Indicators affected

Indicators this person’s verified facts reach. No score contribution is assigned; the observed state is the indicator’s own reading.

Accountability & contradictions

Claims against the record, the type of responsibility, and what is disputed.

Claimed

What happened

Responsibility

What could change this assessment

  • Lifetime coverage has not been assessed: the record reflects stored facts only (0220–0244).

Causal path

Person → Fact → Driver → Indicator. Select a path to inspect its factors; the full network opens on demand.

  1. PersonEratosthenes
  2. FactEratosthenes is appointed to the Alexandrian library under Ptolemy III as later lives report
  3. DriverDigital Learning Access
  1. PersonEratosthenes
  2. FactA measurement of the ecliptic’s obliquity is later credited to Eratosthenes as a distinct astronomical heading
  3. DriverDigital Learning Access
  1. PersonEratosthenes
  2. FactA measurement of Earth’s circumference is later reported under Eratosthenes’s name, principally by Cleomedes
  3. DriverDigital Learning Access

Timeline

The most relevant dated facts, newest first.

  1. 31 December 244 · Digital Learning Access

    Eratosthenes is appointed to the Alexandrian library under Ptolemy III as later lives report

  2. 1 June 240 · Digital Learning Access

    A measurement of the ecliptic’s obliquity is later credited to Eratosthenes as a distinct astronomical heading

  3. 1 January 240 · Digital Learning Access

    A measurement of Earth’s circumference is later reported under Eratosthenes’s name, principally by Cleomedes

  4. 1 January 235 · Digital Learning Access

    A prime-number sieve is later attributed to Eratosthenes; it is not a recovered classroom autograph

  5. 1 June 230 · Digital Learning Access

    A map of the inhabited world with measured intervals is later described as Eratosthenes’s cartographic scheme

  6. 1 January 230 · Digital Learning Access

    A three-book Geography under Eratosthenes’s name is later quoted by Strabo as a completed treatise

Evidence & methodology

How the record is sourced and how the score is derived.

7 of 7 linked facts verified, drawing on 3 distinct sources (0220–0244).

Sources include University of St Andrews, Encyclopaedia Britannica, Perseus Digital Library / Tufts.

Sources

  1. 1.Britannica — EratosthenesEncyclopaedia Britannica
  2. 2.MacTutor — Eratosthenes of CyreneUniversity of St Andrews
  3. 3.Perseus — Strabo, Geography (Jones)Perseus Digital Library / Tufts

The score is formula-derived (Factrail formula v1, version 1.0.0), not an editorial verdict. Read the methodology.

By the Factrail desk · Method: how we source and score · Last reviewed · Sources: 3

Expert analysis

An excerpt; the full analysis opens on request.

Cleomedes, not a classroom globe, is the first public fact about Eratosthenes’s circumference. Britannica at https://www.britannica.com/biography/Eratosthenes (opens in a new tab) and MacTutor at https://mathshistory.st-andrews.ac.uk/Biographies/Eratosthenes/ (opens in a new tab) state that On the Measurement of the Earth is lost and that later writers preserve a Syene–Alexandria method in stadia. That is a source-limit before it is a triumph.

What later reporters actually preserve is a short list. Strabo at https://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:1999.01.0198 (opens in a new tab) and LacusCurtius at https://penelope.uchicago.edu/Thayer/E/Roman/Texts/Strabo/1A*.html (opens in a new tab) quote a three-book Geography and a chart of the inhabited world. ToposText at https://topostext.org/work/144 (opens in a new tab) makes the same Greek-English neighbourhood searchable. Britannica’s Library of Alexandria page at https://www.britannica.com/topic/Library-of-Alexandria (opens in a new tab) and the life itself print a received librarianship under Ptolemy III. Stanford’s ancient astronomy entry at https://plato.stanford.edu/entries/astronomy-cosmology-ancient/ (opens in a new tab) is independent texture for the astronomical neighbourhood, not a causal dataset and not Eratosthenes’s diary.

What is not a lifetime act: Nicomachus’s later arithmetic as a recovered lecture; a JavaScript sieve; a wall map in a science museum; UNESCO or tourism copy about the Pharos; Ptolemy’s second-century Geography as if it were 230 BCE; Hipparchus’s critique as if Eratosthenes wrote it. The sieve is stored as later attributed. The circumference is stored as later reported. Those labels are the point of the catalog, not a demotion of the name.

Related scientific names are bounded. Archimedes corresponds with him in later mathematical tradition. Callimachus is a library predecessor. Ptolemy III is the received royal patron. Strabo is a later carrier. Hipparchus is a later critic of the geographical file. Theon of Alexandria and Cleomedes are later transmitters. Euclid and Aristarchus belong to the same Alexandrian scientific city as received, not as a group photograph.

A library office is not a circumference. A Geography is not a sieve. An obliquity heading is not a map. Conventional year-01-01 dates mark received floruit, not excavated daybooks. Complex contribution is required. Confidence is high that later Greek prose names these headings, medium on autograph wording, low on unique kilometre error. What the score must not say: that he authored Ptolemy; that a school experiment is 240 BCE; that Catasterisms is an undoubted autograph stored here; that a missing Mouseion payroll can be filled by invention.

Later Loeb, UNESCO, and encyclopedia pages are evidence, not additional acts.

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