In parties comply with the principles laid down for the creation of an enforceable contract, they are free to create specific rights and duties of their own that the courts will enforce. A valid contact that is binding must consist of the following: an intention to create a legal relationship, offer, acceptance, consideration, capacity to contract, legality. Contracts must also be free from any vitiating elements such as mistake, misrepresentation, or undue influence. Perhaps to do something for each other or refrain from doing something. Consensus ad idem: agreement as to the subject or object of the contract: the parties must be of one mind and their promises must relate to that subject or object. Some promises are made by people who have no intention of becoming legally obligated to fulfill them not a contract. The intention to create a legal relationship is a presumption in law and must be proven otherwise, if the intention does not exist.