Even though fiduciary duties take the highest position in the spectrum of legal altruism,and legal fiduciary altruism sometimes differs from moral fiduciary altruism,natural law morality is not necessarily useless in helping to explain,determine,and justify concrete rules in fiduciary law.Five specific inspirations,in addition to divergences,can be drawn by a closer look at the seven basic goods of John Finnis'natural law theory.First,the basic good of life may help to determine the boundary of the best interest test under the duty of loyalty.Second,the basic good of play,in particular the distinction between business community and play community may help to justify the separate treatment between civil agency and commercial agency regarding the unconditional power of immediate termination.Third,practical reasonableness may help to explain the rule against set-off under the duty of no conflict.Fourth,different cultural notions of sociability may lead to distinct understandings with regard to the no-profit rule.Fifth,different attitudes towards knowledge in various religious beliefs may create distinct understandings about the burden of informed consent.