D-0002 · Seder Olam is the primary count

When the traditional count and the historians' count disagree, which is primary?

Seder Olam is primary. The historians' count is stored beside it as a second value — never discarded — and every check flags where the two disagree.


Status	Ruled by the owner
Set	20 Tishrei 5787 · 2026-10-01 12:53
Recorded in	held 8a88db89
Rests on	D-0000, D-0001
Affects	the date of every book before the Second Temple, the direction of links between books the two counts date differently
Would change if	A Daas Torah ruling otherwise.

The options on the table

Seder Olam primary; the historians' count stored beside it; disagreements flagged (chosen)
Seder Olam only
The historians' count only, converted to Hebrew years
No primary — every check runs under both counts

Why the count is a decision at all

For most of history the two counts agree once converted. For the Persian period they do not, by about 165 years:

The churban of the First Temple — 3338 by Seder Olam (= 423/422 BCE by arithmetic); 587/586 BCE by the Babylonian king lists (≈ 3175).
Yehoyachin's release (Melachim II 25:27) — 3364 by Seder Olam; 561 BCE by the king lists (≈ 3200).
The Persian kingdom during the Temple — 34 years: "מלכות פרס בפני הבית שלשים וארבע שנה" (Avodah Zarah 9a; Seder Olam Rabbah 30); about 207 years by the historians.

The question was raised first in the Jewish world by Azariah de Rossi, Me'or Einayim (1573), and has been treated by R' Shimon Schwab ("Comparative Jewish Chronology") and Mitchell First (Jewish History in Conflict, 1997).

Why it matters for the graph

The count can reverse an arrow. Yeshayahu 36–39 repeats Melachim II 18–20. By Bava Basra 15a, Chizkiyahu's generation wrote Yeshayahu and Yirmiyahu wrote Melachim — so Yeshayahu's text comes first and Melachim follows it. The academic view holds that Yeshayahu took those chapters from Melachim. Under "the earliest is the source", the direction of that link depends on this decision; with both values stored, the disagreement is shown, not hidden.

Tanach under both counts — the evidence on the day of the ruling

Tradition: who wrote each book by Bava Basra 14b–15a; the years by Seder Olam as usually computed (± a year or two). Academic: mainstream ranges, converted to Hebrew years by arithmetic.

book	wrote it (Bava Basra 14b–15a)	tradition	academic, converted
Torah	Moshe; the last eight verses machlokes	2448–2488	final form ~3300–3350
Yehoshua	Yehoshua; Elazar, then Pinchas finished	~2516	~3140–3200
Shoftim	Shmuel	~2871–2883	~3140–3200
Shmuel	Shmuel; Gad HaChozeh and Nasan HaNavi finished	~2883–2924	~3140–3200
Melachim	Yirmiyahu	~3338–3364	~3140–3201
Yirmiyahu	Yirmiyahu	3298–~3340	~3134–3300
Yechezkel	Anshei Knesses HaGedolah	said 3332–3354; written ~3408–3442	~3168–3200
Yeshayahu	Chizkiyahu and his company	written ~3228 and after	1–39 ~3020–3060; 40–55 ~3220; 56–66 ~3240–3310
Trei Asar	Anshei Knesses HaGedolah	written ~3408–3442	~3000 to ~3300; collected by ~3580
Rus	Shmuel	~2871–2883	~3000–3310, disputed
Tehillim	David, through ten elders	~2884–2924	collection closed ~3560–3600
Iyov	Moshe	2448–2488	~3160–3460
Mishlei, Koheles, Shir HaShirim	Shlomo said; Chizkiyahu's company wrote	said 2924–2964; written ~3228 and after	~3260–3560
Eichah	Yirmiyahu	~3320, before the churban	~3175–3200
Daniel	Anshei Knesses HaGedolah	written ~3408–3442	3594–3597
Esther	Anshei Knesses HaGedolah	~3405	~3360–3560
Ezra–Nechemiah, Divrei HaYamim	Ezra; Nechemiah finished	~3413–3442	~3360–3460

The machlokesim, within the Torah world: whether the Torah was given scroll by scroll or sealed (R' Yochanan and Resh Lakish, Gittin 60a); who wrote the last eight verses (R' Yehuda or R' Nechemiah, and R' Shimon, Bava Basra 15a); Ibn Ezra's "secret of the twelve" (Devarim 1:2); when Iyov lived, or whether he was a parable (Bava Basra 15a–b); whether Malachi is Ezra (Megillah 15a); Yechezkel and Koheles nearly hidden (Shabbos 13b, 30b); Eichah written before the churban (Moed Katan 26a). Between the Torah world and the academy: the documentary hypothesis (Wellhausen, 1878) against R' David Zvi Hoffmann, Umberto Cassuto and R' Mordechai Breuer's "aspects"; Yeshayahu 40–66 (Döderlein 1775, Duhm 1892); Daniel under Antiochus IV (Porphyry; now the academic consensus).

Every traditional line above was read from the library's own text; the academic dates and the derived Seder Olam years are standard references, not yet checked line by line.

The full write-up, with every source and its address: experiments/2026-10-01-tanach-dates.

What rests on this

Generated from the register (docs/decisions/0002-seder-olam-count.md). A changed value is recorded as a new entry; the old one is never overwritten.