兩線物流的困境──關於北魏孝文帝遷都洛陽的新考察

The Dilemma of the Two-Way Logistics on the New Research of Emporer Hsao-Wen’s Moving Luo-Yang City in Bei-Wei Dynasty

孝文遷洛（493）為劃時代之大事，然遷都之事非帝王決意而已，孝文遷洛之可行，還須建構在當時的現實條件之上。北魏由道武帝至孝文帝，都於平城近百年。然平城位處代北，一般而言，環境負載力不比中原，北魏諸帝亦曾取鄴城富盛，有意遷鄴，但因北魏國家戰略北重南輕所需，終不計代價，或開荒實邊，或千里轉輸，克服物資問題，堅守平城，力保根本不失。但隨時局推演，太武統一華北，獻文進軍淮海，南境物資需求亦隨之日增，尤以南境戰守形勢不同北方，南北雙方各自儲糧廣戍，縱然不戰，亦須防備，易流於長期消耗，因此北魏勢須分派相當物資，轉輸向南。獻文平淮北後，制立租輸三等九品之制，當即應對南北兩大物流線的新態勢。此般兩線物流的態勢，令北魏彷彿陷於南北兩線的「物流戰爭」之中，物資供給的壓力大增。更由於當時北敵勢衰，南朝相對轉盛，但北方平城卻有不事生產之眾、競奢炫富之風，南邊鎮戍則用度吃緊、策略保守，使得北魏承擔的物資壓力顯得大而無當、不能應急。於獻文、孝文之世，北魏國內正潛藏此一國家物流轉輸南轅北轍、卻又兩不周全的窘況。對此，北魏雖用增產、轉輸等手段來舒緩問題，但只要仍立都平城、且南北對立不止，北魏即難以突破兩線物流所帶來的困境。反過來說，若要突破此困境，遷都以將兩線物流集中，當為良策。與此同時，當年崔浩所論必須堅守平城的兩大理由，一則北敵強盛、南敵懸遠，二則軍國核心人口不足、不能服眾等，已趨衰微，餘下如保守勢力等政治問題，則較易於克服。至此，孝文帝所受的制約已大為減輕，遷都之可行性，已浮上檯面。要之，孝文帝遷洛之背後，無論統治者們有意無意、或事後成功與否，至少是在追求一個他們認為更有效、更適合當下的組織方式，而這終究無法脫離當時的現況。因此在討論孝文遷洛之時，除少數統治者的意念之外，勢必不能忽略允許、促成孝文成功遷洛所蘊含的諸多現實問題，本文所述的南北兩面物流困境，當為其一。

Relocating the capital to Loa-Yang City is not only based on the Emperor Hsao-Wen’s decision but also constructed on the actual conditions that the empire held. Before relocating the capital, Bei-Wei Dynasty’s capital had been at Pin City for nearly one hundred years. Due to the fact that Pin City was located in the area of Dai-Bei, the environmental endurance was weaker than Central China. However, because the nation strategic policies were mainly focused on the requirements for the north, the government chose to reclamation and transporting supplies for thousands of miles to persist Pin City as the capital by all costs. According to the historic facts, after Emperor Tai-Wu united mid-northern China and Emperor Hsien-Wen led troops into the area of Huai River, supply requirements from the south became more critical, especially when the situations were different from the north. Both the north and the south were storing army provisions to form a military base, which usually turned into an expensive warfare. Therefore, Bei-Wei Dynasty needed to deliver the supplies and transport it to the south. After controlling the area of Huai River, Emperor Hsien-Wen established a tax system that had significance about distribution of supplies, and it immediately responded to the latest situation of the two logistic lines, which were delivered to both the north and the south. The situation of the logistics at both sides greatly increased the pressure to Bei-Wei Dynasty of supplying materials. So during Emperor Hsien-Wen and Emperor Xiao-Wen, it could be said that the Bei-Wei Dynasty fell into a dilemma of logistic matters on both the north and the south sides. Under the dilemma, although Bei-Wei Dynasty attempted to alleviate the problem of supplies with various means, the pressure would not decrease if Ping City was still the capital and the north-south confrontation was not resolved. Moreover, the influence of enemy from the north declined while the enemy from the south grew stronger. In Pin City, there was a group of non-productive people who lived in luxury and competed their income and luxuries with others. But the military expense in the southern front line was tight, which gained the pressure to Bei-Wei Dynasty. This logistic dilemma would promote changes in the existing system of the empire. In my opinion, this dilemma is the foundation of Emperor Xiao-Wen’s relocating the capital to Luo-Yang City, and was also the key to success.