物權行為有價值嗎？基於經濟分析的考察

物權行為獨立性亦是價值判斷問題。基於提升資源配置效率、降低交易成本的理念，物權行為具備獨立必要性。交易安全保護問題上，無因性可有效降低交易成本，功能與善意取得並不重疊。若將後手交易受讓人惡意界定為其知道或應知前手交易存在效力瑕疵事由，基於前手交易效力瑕疵判斷的不確定性，後手交易受讓人會傾向於拒絕交易，此時不存在調查成本，但會產生尋找相似交易的成本。是否承認無因性會影響交易成本與資源配置效率。物權行為無因性是原則，有因性為例外。僅在前手交易轉讓人發生重大誤解，同時後手交易受讓人以不合理價格受讓標的物等例外情形下，才需否定無因性。在返還權利人與義務人的雙邊返還清算關係中，否定無因性會增加破產管理人或債權人的確權成本等費用。在返還權利人與第三人的三邊返還關係中，否定無因性會提升交易成本、返還清算成本。我國民法諸多規則，應立足于物權行為理論的審思，作相應調整。

The independence of real right act is also a matter of value judgment. To enhance resource allocation efficiency and reduce transaction costs, the real right act should be independent. Regarding the transaction security, the abstraction principle can effectively lower transaction costs, and its function does not overlap with bona fide acquisition. If the malice of a subsequent transferee is defined as knowing or having reason to know the existence of validity defects in the prior transaction, the uncertainty in judging such defects would incline the subsequent transferee to refuse the transaction. In this scenario, while investigation costs would not arise, the cost of seeking similar transactions would emerge. Whether to recognize the abstraction principle affects transaction costs and resource allocation efficiency. The abstraction principle constitutes the general rule, with causality being the exception. Only in exceptional cases—such as when the prior transferor acted under a significant mistake and the subsequent transferee acquired the subject matter at an unreasonable price—should the abstraction principle be negated. In bilateral restitution relationship, negating the abstraction principle would increase costs such as the confirmation expenses borne by bankruptcy administrators or creditors. In trilateral restitution relationships, negating the abstraction principle would raise both transaction costs and restitution settlement costs. Many rules in China's civil law should be re-examined and adjusted based on a thoughtful consideration of the theory of real right act.