To constitute an obligation enforceable in law, the rights and liabilities given and imposed must be definite. In other words, it must relate to definite acts and forbearances. The freedom of the person bound by an obligation is not curtailed generally, but is limited in reference to some particular act or series or class of acts. If the thing to be done or forborne is so indefinite or uncertain that the court cannot say what was agreed upon, it cannot enforce the agreement.18 An agreement not enforceable creates no obligation, and therefore cannot result in contract.
The Thing to be Done or Forborne must be Reducible to a Money Value The matter of the obligation - that is, the thing to be done or forborne - must possess, or must be reducible to, a pecuniary value. It must have some ascertainable value, in order to distinguish legal from moral and social relations. Gratitude for a past kindness cannot be measured by any standard of value, nor can annoyance and disappointment, caused by the breach of a social-engagement. Courts of law can only deal with matters to which the parties have attached an importance estimable by a standard of value of which the courts may take cognizance.
5. An agreement resulting in contract is that form of agreement which directly contemplates and creates an obligation; and the contractual obligation is that form of obligation which springs directly from agreement.
17 Anson, Cont (4th Ed.) 5. 18 See post, p. 54.