The Theory of Determing the Rule of Subject Obligation and Possession: Different forms of determining the consideration

The subject of obligation and possesstion should be definite, for instance, in a bilateral contract, consideration must be definite and if it is not so, the contract will not be concluded and that makes it void (Article: 216,338 and 384 civil code if Iran). The consideration may not be mentioned either due to carelessness or oblivion or when the two parties intentionally refuse to mention it in the contract and leave it to expert's view, customary law, common practices or well-known norms to determine it. When determination of consideration or price of a contract requires expert surveying and estimation or accounting operations, the involved parties are compelled to leave this task to a later time and not to mention it in the contract. The question in such a situation is whether these kinds of contracts are valid and binding or either of the parties can refuse to perform his/her commitments by resorting just to the pretext that the contract is invalid or the agreements is defected. At ention must be paid to the fact that not mentioning a price in the contract does not always mean that the consideration is indefinite and it depends on the agreement between the parties involved. Agreement on the methods and rule of determining the subject of obligation or possesstion, that is to say, specifying the rule and criterion for determining the subject of obligation or possesstion is sufficient because it is thus determined with that rule and such contracts cannot be considered as null and void with the pretext that the consideration is indefinite. In legal obligations and possesstions assigned by the law, it is usually preferable to determine methods and mention an exact price or cost. Not mentioning the subject of obligation or possesstion does not nullify the terms or the contract and the terms even in the Islamic jurisprudence and as it is quite well known they do not consider the indefinite condition as nullifying the terms or the contract. Since the indefinite condition cannot be considered a valid condition because obligation of an obliged person to perform an indefinite act is impossible, the condition shall thus be null and void but in cases where the ambiguity of the condition can be removed in future and it can be performed, the condition is not null and void.