信義義務的一般理論及其在中國法上的展開

信義義務起源於信託領域，忠實義務是其核心內容。從抽象意義來看，忠實義務的基本要求包括受託人為受益人的唯一利益或最佳利益服務，以及禁止利益衝突。注意義務的標準高於忠實義務，但內涵並不明確，共計有商業判斷規則、謹慎投資人標準、善良管理人的注意義務、誠實信用四種學說可供參考。英美法上，違反信義義務的特殊法律責任包括衡平法上的返還獲利以及擬制信託，它們具有懲罰性。中國法上，忠實義務體現為一系列禁止性規範，注意義務則呈現為一般條款與不確定概念，違反信義義務的法律後果屬於違反保護他人法律的侵權類型。注意義務具體化可以適用比例原則以及動態系統論。中國法可以在醫療等領域推廣適用信義義務。

The fiduciary duty originates from certain typical cases in trust law, and the duty of loyalty constitutes its core content. In the abstract, the duty of loyalty requires fiduciaries to act for the beneficiaries sole interest or best interest and to avoid conflicts of interest. Although its content is not clear-cut, generally the duty of care has a higher requirement than duty of loyalty, and in both American law and Roman law, four doctrines, i. e. business judgment rule, aprudent investor rule, the duty of care of good managers and good faith, can be cited for reference in its application. In American law, the special consequences of breach of fiduciary duty include accounting of profits and constructive trust, both of which are punitive measures. In Chinese law, the duty of loyalty take the forms of a series of prohibitive norms while the duty of care emerges as a general clause and unclear concept, and the breach of fiduciary duty appertains to a tort of violation of law for protecting others. The theories of proportional principle and flexible system can be used in embodying the duty of care. In Chinese law, fiduciary duty can also be applied in other areas, such as medical relation.