HARVARD LAW REVIEW. VOL. XII. MARCH 25, 1899. NO. 8 TWO THEORIES OF CONSIDERATION. I. Unilateral Contracts. CONSIDERATION, according to the traditional definition, is either a detriment incurred by the promisee or a benefit received by the promisor in exchange for the promise. Professor Langdell has pointed out the irrelevancy of the notion of benefit to the promisor, and makes detriment to the promisee the uni- versal test of consideration. The simplified definition has met with much favor. It is concise, and it preserves the historic con- nection between the modern simple contract and the ancient assumpsit in its primitive form of an action for damage to a promisee by a deceitful promisor. In one respect only does the definition leave anything to desire. What is to be understood by detriment? The incurring of a detriment by the promisee involves of neces- sity a change of position on his part ; there must be some act or some forbearance by him. But will every act or every forbearance be a detriment, or must the word be restricted to certain acts and forbearances? It is certainly a common opinion that the word is to be interpreted in the restricted sense and cannot properly include an act or forbearance already due from the promisee by reason of some pre-existing legal obligation. The inability of the writer to reconcile this opinion with the decided cases has led him to give to detriment its widest interpetation and to define con- 67
