Sec. 51. Consideration May Consist In Promise Or Act

The detriment sustained by one as a consideration may be either his promise or his act, whichever is responsive to the expression of the other side; but a promise to be a consideration must be a promise to do or refrain from doing a definite thing within an ascertainable time.

A promise on one side is a good consideration for a promise upon the other. In other words, it is not necessarily doing an act, but may be the making of a promise to do an act, which may constitute the consideration. This depends upon the requirements of the offer and acceptance. In all bilateral contracts the consideration for the promise of each is the promise of the other.

A promise cannot be a good consideration unless it binds one within a definite time to do or refrain from doing a definite thing, - a promise cannot be a considera-tion unless it is definite enough to be broken.

Example 41. A agreed to sell and K to buy at stipulated prices 10,000 barrels of oil as the buyer might desire them. Held to be no contract. "But suppose Kirk & Company do not desire, and do not order, or order in such quantities as would require a hundred years to complete

- is there any way open to the defendant to put plaintiffs in default?" 74

Example 42. N agreed to sell and K to buy all of a certain quality of pig iron which K would need, use or consume in its business during the coming season from July 9, 1879, to July 1, 1880. Held, a good contract. "It cannot be said that K was not bound by the contract. It has no right to purchase iron elsewhere for use in its business." 75

Where the promise is to sell, and the corresponding promise to buy, the needs of a future period, the period should be definite and the amount should be all that the buyer needs or all that he needs up to a certain amount, or, of course, a prescribed amount. It has been argued that it is not certain that the buyer will need any amount, and this has been answered by the statement that in all probability he will. But that answer is not the correct one. If the seller promises to sell and the buyer to buy, his needs during a certain future period, the consideration is in fact that the seller must stand ready to deliver at the prices and terms agreed on all that the buyer may order, and the buyer must, if he needs any of such commodity buy it from this seller at the prices and terms agreed upon. He gives up his right to buy elsewhere on possibly better terms.

74. American Cotton Oil Co. v. Kirk, 68 Fed. 791.

75. Nat. Furn. Co. v. Keystone Mfg. Co., 110 111. 427.

Sec. 52. Past Act

An act done prior to the promise sought to be enforced and therefore without reference to it does not constitute a legal detriment and therefore is not a consideration to support such subsequent promise and make it enforceable.

If one performs an act with no right to claim anything for doing it, and after that time a promise to pay him for doing it is made, such promise is without consideration and cannot be enforced. No detriment has been sustained by the promisee on the faith of the promise. One must not confuse such cases with the cases in which, where one does an act, he does it under such circumstances that he may reasonably demand compensation therefor. In such case we know there was really a promise, though not expressed, in reliance upon which the act was done. But if the act is without reference to receiving the reward afterwards promised, the subsequent promise is an unenforceable promise.

Example 43. A father made a promise of compensation to a stranger who had cared for his son as an act of kindness. He then refused to perform the promise. Held, no contract.76

Where a discharge in bankruptcy has been obtained, or the statute of limitations has run, a subsequent promise to pay is enforceable, though in some states it must be in writing.

Sec. 53. Performance Of Or Promise To Perform Obligations Imposed By Law

The performance of or promise to perform an act required of one as a legal duty cannot be a legal detriment, and is therefore not a consideration.

Where one does an act which the law requires of him, he cannot claim a promise of reward made to him for doing it. Take, for instance, the case of a reward offered for the capture of an accused person to an officer whose public duty is to capture such person if he can. Such reward is not recoverable, not only because there is no consideration, but because public policy opposes rewards in such cases. This is true even though the officer actually exercised a greater degree of diligence than he would otherwise have done. An officer cannot bargain in respect to his zeal and graduate it according to the remuneration offered.77

76. Mills v. Wyman, 3 Pick (Mass.) 207.

If an officer does that which his legal duty does not require of him pursuant to an offer he may recover. This would be the case where a fireman at the risk of his own life, made a rescue pursuant to promise of reward made him.

Sec. 54. Promise To Perform Unexecuted Contract

A promise to perform or the performance of that which one is under an existing contract to perform is not a good consideration.

Suppose that A has contracted with B, that he will dig a cellar for B, within a certain time at a certain price. In the progress of the work, A comes upon a substratum of shale on whose existence he had not figured. To dig the cellar will require a greater expense than that of his original calculations, and he will lose money on the project. He therefore informs B that he will not proceed further unless B will pay him $100.00 in addition to the original contract price. To this B, being in a hurry for the cellar, assents. He refuses, however, to pay more than the original contract price. Can A force him to pay the $100 ? B's argument is that A was already under a contract to do this work, and if he offered him $100 for doing it, his promise had no legal effect, because A suffered no detriment. He did nothing he was not already bound to do. This is the view of many of the courts.78 Some, however, allow a recovery where unforeseen circumstances arise (as in the above case) which make the demand justifiable.70

77. Hogan v. Stophlet, 179 111. 150.

It is always permissible for parties to rescind an old agreement and substitute a new one, as where A having agreed to put in single doors in B's dwelling, afterwards for a larger price, agrees to put in double doors. In such a case, there is no trouble in finding mutual considerations. But a mere promise to increase the contract price for no other reason than that the other party regrets his contract and threatens to break it, is unenforceable.