In criminal law, the inchoate crime of conspiracy requires an agreement to commit an illegal act. An agreement in this context should not be explicit; On the contrary, the facts and circumstances of the case can rather be inferred from a meeting of spirits. In addition, an agreement is not applicable. In California, the distinction between a final agreement and an agreement depends on the objective intent of the parties. When an agreement is written, the courts determine the intent of the parties by the clear meaning of the words of the instrument. As a general rule, courts are not in a position to balance the «proportionality» of the consideration, provided that the consideration is determined as «sufficient», the adequacy being defined as an exercise in legal review, while «adequacy» is subjective fairness or equivalence. For example, consent to the sale of a car for a pfennig may constitute a binding contract (although the transaction is an attempt to avoid taxes, it is treated by the tax authorities as if a market price had been paid).  Parties may do so for tax purposes and attempt to conceal donations in the form of contracts. This is called the peppercorn rule, but in some legal systems, the penny may be an insufficient nominal consideration. An exception to the adequacy rule is money, a debt that must always pay in full for «compliance and satisfaction.»     Finally, a modern concern that has grown in contract law is the increasing use of a particular type of contract called «contract contracts» or «formal contracts».
This type of contract may be beneficial to some parties, due to the convenience and ability of the strong party in a case to force the terms of the contract to a weaker party. For example, mortgage contracts, leases, online sales or notification contracts, etc. In some cases, the courts consider these membership contracts with particular scrutiny because of the possibility of unequal bargaining power, injustice and unacceptable. An agreement is an expression of mutual agreement between two or more people.