再論《合同法》第121條的存廢－－以履行輔助人責任論為視角

A Review on Article 121 of the Contract Law from the Theoretical Perspective of Obligor's Obligation for Performance Assistant

債務人為履行輔助人的不當履行負擔合同責任的理論基礎，來自債權人對合同上之預見的尊重，即債務人得以免責的諸項要件不會因其役使第三人而發生變更。其實定法依據是有關違約責任的一般規定－－《合同法》第107條，並不需要《合同法》第121條或者其他的實定法規定補強。出於政策考量在某些情形或許需要債務人為非履行輔助人之行為負擔特別保障責任，但這時需要特別立法，《合同法》第121條依然全無用武之地。

The theoretical basis for an obligor to bear contractual obligations for his performance assistant's misfeasance comes from the obligee's respect for the contractual foreseeability, namely, the criteria of exception from liability of the obligor wouldn't change because he employs a third person. Its basis in positive law is article 107 of the Contract Law, which doesn't need the reinforcement of article 121 or any other provision. For policy considerations, an obligor may need to bear special guarantee obligations for acts of a non-performance assistant in certain circumstances. However, what needed here are special legislations, and Article 121 is still completely useless.