About the Old Master老夫之道

Before any reading, the chart must be correct. And to be correct, it must be cast with a trustworthy calculation tool — never left to an AI to "guess." Zi Wei Dou Shu has strict rules of star placement: each star follows a fixed formula based on day-hour-month-year of birth, with no room for inspiration or improvisation. One star wrong and the entire chart drifts.

Thien Co Cac uses **iztro** — an open-source TypeScript library by Sylar Long under MIT license, with over 2,000 stars on GitHub, used as the digital Zi Wei engine across countless Chinese-language apps. Each time you enter a birth time, the chart is recomputed from scratch on the server — deterministic, reproducible.

Concretely: enter day-hour-year-month-gender-calendar type → iztro produces 12 palaces, every major-minor-helper star position, the four transformations (Lu, Quan, Ke, Ji), Major and Annual cycles. All by classical formulae. The Old Master only reads after the chart is correct — never lets the AI invent a star.

Take this seriously before trusting any Zi Wei site. **Language AIs — even powerful ones like GPT, Claude, Gemini — frequently get the answer wrong when asked "which palace is Zi Wei in for a person born on date X."** Why? Language models learn from text, with no internal calculation module. They don't truly know the placement rules — they patch together what they've seen most often. Ask ten times, get ten different charts, none accurate.

This is **AI hallucination**. For soft questions — "describe the personality of someone with Tian Xiang in the Life Palace" — AI does well, because it's a synthesis of text. For hard questions — "born 1990-09-12 at the Hai hour, place the stars" — AI fabricates a chart that sounds correct but is utterly wrong. Without deep Zi Wei knowledge, you can't catch the error.

So Thien Co Cac strictly separates the two: **iztro** handles the hard math (star placement formulae); **AI** only handles the soft reading (interpreting the meanings of stars already correctly placed). You can rest assured: the chart you see is a classical, correct chart — not a hallucinated one.

Zi Wei Dou Shu has evolved over a thousand years and birthed many schools. Each illuminates a different layer of qi, each with strengths and blind spots. Many sites use only one — usually the popular San He school — leaving readings one-sided. Thien Co Cac combines the three major modern schools:

Reading the Old Master, you'll sometimes hear "in San He terms…", "Zhong Zhou sees it as…", "Si Hua activates here…". This isn't showing off — it's how the Old Master ensures you don't view your chart through a narrow lens.

Huyen Tri's interpretations don't run on Western GPT, Claude, or Gemini — they run on China's strongest AI models: DeepSeek, Qwen (Alibaba), GLM (Zhipu), Yi (01.AI). Not for cost — for expertise.

Zi Wei Dou Shu is a Chinese cultural inheritance. Every classical text — Chen Xi Yi's Comprehensive Book of Zi Wei Dou Shu, the Zhong Zhou and Si Hua manuals, the secret texts of the Eastern and Western schools — is written in classical Chinese. Chinese AI models, trained on vast Chinese corpora, understand the terminology natively:

Western models learn Zi Wei through translation — usually thin, losing nuance. Ask GPT about "Tan Lang meeting Wu Qu" and it translates the question into English first, answers, then translates back — two layers of translation, 30% loss. Chinese models read the original texts directly.

• · Understand mutagens (化禄, 化权, 化科, 化忌) precisely from the original sources.
• · Distinguish classical patterns ("Wu Sha tong xing", "Zi Po chu wai", "Tong Ju Chou Wei"…) by original wording.
• · Reading tone closer to classical texts — never "Americanized" into Western astrology style.

Finally: the prompts Thien Co Cac sends to the AI are also written in Chinese (modern Hanyu blended with classical phrasing). You don't see them directly — but that's why the Vietnamese reading you read carries a classical soul: the source is Chinese, only translated to Vietnamese at the very last step.