The Distinction between Obligation and Duty in Private Law

Obligations and duties are often confused. However, their distinction is fundamental. The present essay proposes to distinguish the two concepts by drawing the criterion of distinction in the structure and the source of the situation of passivity. In terms of structure, the obligation differs from the duty by the existence of a determined debtor and creditor. The structure of the obligation separates it from duties that do not exist between two determined parties. Nevertheless, this first criterion is insufficient. It does not make it possible to distinguish between obligations and duties that exist between determined parties. Therefore, it must be combined with a second criterion that is drawn in the source of the situation of passivity. In terms of its source, obligations derive from the rule of law or the intervention of the debtor. The source of the obligation separates it from non-statutory duties and non-legal duties. The distinction between obligations and duties is useful. It has practical use within liability proceedings and outside such proceedings. However, the present essay does not merely highlight the differences between obligations and duties. Their distinction is flexible, in that it reveals similarities between the two concepts. Separated by their structure and their source, obligations and duties have a similar object and a similar subject. In effect, the same person may be required to accomplish the same performance under an obligation or under a duty.