ʾABŪ SAʿĪD AL-SIǦZĪ AND THE “STRUCTURE OF THE ORBS,” THE EARLIEST KNOWN WORK ON <i>HAYʾA</i>
Bibliographic record
Abstract
Abstract ʾAbū Saʿīd al-Siǧzī was a prominent fourth/tenth century astronomer and mathematician who was one of the first contributors to the new genre of ʿilm al-hay ʾa (science of the configuration). However, little is known about the initial steps taken in the formation of the discipline, or its independence from other astronomical writings and practices. In this paper, I will discuss new findings about Siǧzī’s life to determine details of his biography and a more precise time period for his scientific activities. I then describe, for the first time, a composition in theoretical astronomy from the fourth/tenth century, the “Structure of the orbs” ( Tarkīb al-aflāk ) by Siǧzī to show its place in the formation of the discipline of ʿilm al-hay ʾa , comparing Siǧzī’s book to the earlier work of al-Farġānī on the size of the earth and the number of celestial spheres. I conclude that Siǧzī’s Tarkīb al-aflāk is the earliest known example of a book that contains only topics found in later hay ʾa and may be the first appearance of the ninth celestial orb that became standard in the later genre.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.004 | 0.013 |
| Scholarly communication | 0.003 | 0.004 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.001 | 0.002 |
| Insufficient payload (model declined to judge) | 0.003 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".