睡虎地秦簡《日書》〈土忌〉篇數術考釋

A Study of the Shu-shu Principles Discussed in the Tu-ji Chapters of the Ri-shu (Daybook) on Qin Dynasty Bamboo Slips from the Shui-hu-di

睡虎地秦簡《日書》出土迄今已三十餘年，研究者眾多，然而一些研究在史料的運用上仍存在不少問題，其中最重要的是對數術原理的瞭解不足，使史料意義未能得到充分的發掘，對社會現象背後的社會心理，以及當時人對時日宜忌之理解等問題皆未觸及。因此運用數術原理，對具體的時日宜忌加以解析，是《日書》研究中亟待突破的一環。本文即從數術原理的角度考釋《日書》甲種中的兩篇〈土忌〉。》〈土忌〉諸條，不但反映當時人對「動土」宜忌的信仰，且因「土」為五行之一，也為這些信仰的數術原理提供了五行生克關係的線索。透過本文數術原理的討論，〈土忌〉中以往難以讀通的一些條文，如「招榣今日」、「地杓」諸條，也得到較合理的解釋。本文除了嘗試瞭解各神煞的數術原理外，也企圖透過神煞中干支排列的規律性，修正並補充不完整的簡文，還原神煞的原貌。其中如「臽日」、「土徼」的確認與修正，「招榣合日」、「地杓」的解析與辨識，及其他各神煞原理的考證，都可以補以往研究之不足。本文在分析過程中，發現《日書》中的五行關係已非常成熟。在「招榣合日」的考證中，可以看出除以往學者注目的生克關係外，後世五行關係中的「害」、「合」等關係，也已出現。同時也可看出一個神煞，經不同關係（衝破、害、合）的變形，而衍生出新神煞的情形，如「月建」與「地杓」、「招榣」與「招榣合」。這些數術原理的發掘，呈現了《日書》的深度內涵，值得我們繼續探索。

More than thirty years have passed since the excavation of the Qin dynasty Ri-shu (日書, Daybook) from Shui-hu-di, and while much research has been done, various questions concerning the interpretation of the Ri-shu remain unanswered. In particular, research on the shu-shu (數術) principles in the Ri-shu is a crucial area awaiting further study. Indeed, the use of the shu-shu principles for understanding the logic behind the selection of certain days as suitable or as highly inappropriate for certain activities is one of the primary areas needing further research. Why, for example, were taboos observed on certain days for excursions while other days were deemed very suitable for this activity? Analyzing the shu-shu principles, this paper will examine the tu-ji (土忌) chapters of the Ri-shu. Tu-ji literally means ''the taboos on breaking the ground,'' such as building or fixing a house or digging a gully. The tu-ji chapters reflect the beliefs and taboos on ''breaking the ground'' prevalent in society at the time. Furthermore, because tu (土, meaning soil, earth, ground, or land) is one of the ''Five Agents'' (五行), research on tu-ji allows us to understand the complex relationships among the Five Agents. Analysis of the tu-ji thus provides us with crucial insight for understanding how and why a certain day was selected as suitable or as unsuitable for doing something. By discussing the shu-shu principles, various seemingly enigmatic texts in the tu-ji chapters can thus be further clarified. The selection of certain days for doing something (or abstaining from some activity) formed a system called shen-sha (神煞) , literally meaning fierce god. The shen-sha system resembled the operation of stars in terms of its regularity and circulation, and was believed to be controlled by god. In addition to the exploration of the principles of shen-sha, we can use the regularity of shen-sha to correct and supplement fragmented characters on the bamboo slips as well as to restore the original contents of shen-sha. Textual research of shen-sha such as xian-ri (臽日) , tu-jiao (土徼) , zhao-yao-he-ri (招榣合日) , and di-biao (地杓) reveals that during the Qin dynasty the Five Agents system was already well established. The relationship among the Five Agents largely remained the same throughout later periods, as documented in subsequent historical works. However, we also find some shen-sha metamorphosing into new shen-sha. Such phenomena highlight the depth and complexity of the Ri-shu, which calls for further research.