本文以北京大學整編之竹簡《揕輿》作為研究對象，主要針對該文的實質內容，進行詳要之分析，確定其擇日占驗推衍吉凶的本來性質，釐析其推用方法的主要取向，並與傳世文獻進行互參，以勾勒其實質之面貌。竹簡《揕輿》展現出堪輿作為擇日占驗之術，透過觀測天象，調理自然規律，行其通天道以明人事之功。本於天文星象、曆法節候的時空衍化的科學化理解，天干地支、五行方位知識系統之運用，呼應陰陽變化之思想與原理作為理論根本，以月建陰陽順逆之說與陰陽大會的基本法則，鳩理時日之宜忌，開展出一套趨吉避凶的推占體系。

This study is on the bamboo slips Geomancy complied by Peking University. The aim is to make a detailed analysis of its content, to verify its nature of divination and date selection, to clarify the main methods of its practice, and to get a general picture of it through literature review. The bamboo slips reveal that geomancy, as a method of date selection and divination from observing heavenly bodies and natural rules, was used to understand the laws of the Nature and human affairs. It is a scientific understanding of astronomy, astrology, and calendar systems. It exercises the knowledge of the heavenly stem and earthly branch and the five element systems. It corresponds with the principles of the changes of yin and yang and takes them as its basis. With the generating and overcoming theories of month names and the basic principles of the great encounter of yin and yang, it exhibits what is appropriate or inappropriate for a certain date or time and develops a divination system with the purpose of getting close to good fortune and avoiding bad luck.