日本民法中的錯誤論－－兼析法律的經濟分析在民法解釋中的界限

The Theory on Mistake of Contract in Japanese Civil Law: With the Range of Economic Analysis of Law in the Interpretation of Civil Law

我國的司法判決中，法院在處理重大誤解的案件時開始使用“行為的前提”甚至經濟學中“風險承擔”等概念，但這些概念在現存的以“內容錯誤”為核心的概念體系中如何定位，“前提”和“風險”之間又是怎樣的適用關係，還欠缺細緻的說明。筆者通過借鑒日本民法中有關錯誤論的研究經驗，嘗試對上述概念進行理論構成。“行為的前提”指的是能夠影響合同對價的雙方動機錯誤。對於動機錯誤是否可以通過錯誤條款（日本民法第95條）獲得救濟，日本法上經歷了二元論、一元論、新二元論、多元論的發展歷程。在日本學界，將影響合同對價的“中間合意”從動機中抽離出來作為獨立的救濟理由是學說發展的潮流，這一結論與我國司法判決的動向是一致的。最後，筆者以“前提”理論和“風險承擔”思想間的關係為例，嘗試回答經濟分析的方法在民法解釋論中合理適用的界限。

A recent trend in Chinese judicial decisions on mistakes of contract can be observed that the courts show great tolerance to such cases in which both parties entered into a contract under the same mistaken “precondition”, but deny the alleviation when one of the parties has taken the “risk” of the mistake. Some theoretical problems still remain to be explained. First, the mistaken “precondition” could also be caught as some kind of “risk”. Second, can contract be avoided only because of some mistaken “preconditions” which merely concern motives of the contract? The author made a comparative study in this thesis on the Japanese civil law trying to find out some plausible interpretation to the legal phenomenon. In Japan the so called “middle consents”, which affected the consideration of the contract, are nowadays considered apart from pure motives and alleviated. This quite corresponds to the resent trend in China. At last the author tried to discover the margin and boundary of the method of “law and economics” in the interpretation of civil law by analyzing the relation between “preconditions” and “risk of mistake”.