---
title: "Taixuanjing (81 Tetragrams) (太玄經)"
method: GET
path: "/api/trpc/taixuan.compute"
tags: ["Eastern"]
---

# Taixuanjing (81 Tetragrams) (太玄經)

`GET /api/trpc/taixuan.compute`

## Request

- Base URL: `https://api.asktian.com`
- URL: `https://api.asktian.com/api/trpc/taixuan.compute`
- Auth: HTTP bearer

Yang Xiong's Canon of Supreme Mystery (2 BCE) — the Han dynasty's deliberate counter-canon to the I Ching: 81 TERNARY tetragrams (four lines of heaven/earth/man) in place of 64 binary hexagrams. The received sequence IS base-3 counting (中 #1 = 1·1·1·1 … 養 #81 = 3·3·3·3, a law asserted at load), the four lines read top-down as the text's own 方 region · 州 province · 部 department · 家 family hierarchy (3→9→27→81), and each 首 carries 9 appraisals (贊) — two to a day-and-night, so the 729 appraisals span 364½ days from the WINTER SOLSTICE where 中 opens the yang breath, closed by the intercalary 踦 and 嬴 appraisals to the quarter-remainder calendar's 365¼. Query by tetragram number, by four cast lines, or by date (the governing 首 of the Taixuan year, anchored to the real astronomical solstice — the summer solstice provably lands in 應 #41, the all-earth midpoint). Names double-sourced: the received text ≡ the Unicode Tai Xuan Jing block with Nylan's canonical translations. The full 準 hexagram correspondence table is deferred, not guessed.

Cost: 2 TIAN Points per call. tRPC procedure `taixuan.compute`.

## Query parameters

- `input` string

## Response `200`

tRPC result envelope

- TrpcResult: tRPC HTTP response envelope.
  - `result` object
    - `data` object: The procedure's return value (system-specific).

---

[API](https://skmtc.dev/asktian/apis/asktian-metaphysics-api.md) · [All operations](https://skmtc.dev/asktian/apis/asktian-metaphysics-api/llms.txt) · [OpenAPI document](https://skmtc.dev/asktian/apis/asktian-metaphysics-api/revisions/3c8fdc979206?raw)