<論説>九世紀中葉の公文勘会制整備 --文書行政の浸透と関連して--

Abstract

調庸制は日本古代律令国家の収取制度の一角を占め、中央財政を支えていた。調庸物の納入に際しては、物実の検査に加え、帳簿などを用いた公文勘会によって監査がなされるが、これまでは天長・承和年間に公文勘会制変質の画期が求められてきた。しかし、先行研究が指摘した重層的勘会構造の成立および国郡司の分業体制はともに八世紀後半から確認され、令制下の基本原則であった。また斉衡年間には諸司諸家から主計寮へ勘会権の一部が委譲されたものの、重層的勘会構造の大枠は保たれた。ゆえに当該期は、多少の逸脱を含みながらも、未進の恒常化という現実を前提とした律令制的公文勘会制の一大整備期とみるべきである。これらの政策は九世紀前葉の政策と連続性があり、その背景には日本古代社会全体への文書行政の浸透があった。しかし、公文勘会制整備政策は九世紀の多くの政策と同じく現実の追認に端を発しており、未進の増大を実際には抑制できなかった。

In this paper, I examine the significance of the development of the kumon kankai 公文勘会system during the mid ninth century in relation to the penetration of a document-based bureaucratic administration throughout ancient Japanese society. The kumon kankai system conducted audits of official documents submitted to the central government from various provinces, and among these, those related to the system of paying taxes in kind or labor, chōyōsei 調庸制, will be examined in this article. Previous research has generally seen the kumon kankai system as having been transformed in the mid ninth century and in a negative light as a regression from the provisions of the Ritsuryō state. This understanding is premised on the following two points that were thought to have occurred in the mid ninth century. The first was the collapse of the principle that envoys should enter the capital with taxes and documents in hand and that their responsibilities were shifted, becoming part of the duties of provincial and district officials. The second point is that documents that functioned as receipts such the henshō 返抄, a certificate of completion of payment, and the shūbun 収文, a receipt for payment in kind, came to provide a multilayered structure so the kankai system would itself would be multi-layered. However, both the multi-layered structure of the system and the division of labor of the provincial and district officials have been confirmed to have existed in the second half of the eighth century, and thus they are thought to have been basic structures of the Ritsuryō system. Therefore, the understanding of earlier research is not supported by the facts. The development of the kumon kankai system in the mid ninth century is important in that the multi-layered kankai structure that had existed customarily for some time was officially recognized. This was intended to improve communications between the various officials and houses, the provinces, and the Taxation Bureau by making reliable records of the tax payment process on the premise that delays in the payment of taxes in kind would lead to a failure to pay taxes fully and this would become chronic. In the process of maintenance of the kankai system, some of the authority of the lower-ranking official families in the lower levels of the kankai structure was transferred to the higher level of the Taxation Bureau. Although the multi-layered structure of various officials and families was dissolved, the multi-layered kankai structure itself was maintained at least until the middle of the tenth century. From the above, it can be said that the tax collection system envisioned in the ninth century was a policy aimed at maintaining and restoring the Ritsuryō system of tax collection, even though it included elements that deviated from the Ritsuryō system, and the middle of the ninth century can be evaluated as a period of major development of the kumon kankai system within the Ritsuryō system. These policies maintained the orientation toward abstract and rational fiscal management of the early ninth century, and accompanying them came the use of uniform documents that spread through the tax collection system and became standardized. Behind these developments was the heightened trust in recorded information due to the penetration of document-based administration into ancient Japanese society. However, the development of the kumon kankai system also had a strong element of institutional reform designed to confirm the existing reality, and it did not lead to basic change in the Ritsuryō system of tax collection or a transformation into a new system. The dysfunction of the tax collection system continued thereafter, and the impact of these policies on the tax collection system cannot be overestimated.