《道德经》第七十九章
和大怨，必有余怨﹔报怨以德，安可以为善。
是以圣人执左契，而不责于人。有德司契，无德司彻。天道无亲，常与善人。
《Tao-Te Ching》Chapter 79
When a reconciliation is effected（between two parties）after a great animosity，there is sure to be a grudge remaining（in the mind of the one who was wrong）。And how can this be beneficial（to the other）？
Therefore（to guard against this），the sage keeps the left-hand portion of the record of the engagement，and does not insist on the（speedy）fulfilment of it by the other party.（So），he who has the attributes（of the Tao）regards（only）the conditions of the engagement，while he who has not those attributes regards only the conditions favourable to himself.
In the Way of Heaven，there is no partiality of love；it is always on the side of the good man.
【易解】
和解深重的怨恨，必然还会残留难以消解的余怨，这怎么能算是完善？因此，圣人凭契约关系来确立自己的主导地位，绝不无依据地责成于人。有德的统治监察契约的订立与履行，无德的统治注重于税赋的收敛，只索取无条件的单向供奉。完善的系统运营机理是普遍平等，无所偏爱，但又具有奖掖良善的健全功效。
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