Sukuyo history: reading the Sukuyōkyō and its commentary
Sukuyo history begins with the surviving T1299 text and its commentary; modern calculators do not all preserve one unchanged ancient method.
Overview
Read the translation attribution, commentary and month table as distinct evidence before constructing a transmission story.
At a glance
- Primary text
- T1299
- Attribution in this edition
- Amoghavajra / 不空
- Commentary
- Yang Jingfeng / 揚景風
What survives in this edition?
The heading attributes the translation to 不空, while the preface names 揚景風 as revising and annotating it. Translation and commentary are therefore distinct layers.
A modern web transcription is an access point to that edition, not an original manuscript or proof of a single line of transmission.
What subjects does the text contain?
Its chapters combine mansion and palace arrangements, birth descriptions, day activities, relative cycles and weekday traditions.
This breadth matters: modern personality articles describe only one part of the material.
Why the commentary matters
The notes explicitly compare Indian and Chinese astronomical descriptions. Differences are discussed within the text rather than erased.
When a modern explanation quotes a short sentence, check whether it comes from the main passage or the commentary.
Ancient tables and modern tools
The first-day row of the volume-one month table begins with 虛. OpenFate’s modern 27-mansion month-start convention begins with 室.
This is a documented difference, not a reason to silently rewrite the old text or the product’s saved calculation.
How to investigate transmission
A claim about transmission to Japan needs a dated document or readable scholarly argument. The preface alone cannot establish every later Japanese school.
This introductory page therefore keeps detailed founder and lineage claims open rather than filling a timeline from unsourced retellings.
Audit a historical claim
For any date or lineage claim, note the edition, volume, passage, named speaker and whether the wording is main text or commentary. Then check whether the cited passage actually states the claim.
If the evidence establishes only that T1299 contains a rule, do not extend it into an undocumented claim about every later form of Sukuyo.
Sources and editorial basis
- 宿曜經 · T1299 卷上卷上 opening title and preface: 不空 translation attribution, 揚景風 annotation;「大唐月建圖」first-day row.Historical text for mansion names and calendar tables. Its table is not identical to OpenFate’s modern 27-mansion lookup; it does not establish predictive validity.
- OpenFate Sukuyo calculator and calculation conventionEditorial code check 2026-09-10, policy 1.0.0: history; policy.ts, constants.ts, engine.ts and traditional-cycles.ts. Product settings are not an independent historical authority; practical examples are OpenFate editorial applications.Product-specific input and output reference. Editorial checks also inspected policy 1.0.0 and the month-start constants on 2026-09-10; those implementation checks are not an independent traditional authority.