On this basis, in 1804, France enacted the first bourgeois civil code, which made detailed provisions on the contract legal system for regulating commodity relations, marking the formal formation of modern contract law in civil law countries.
1900, Germany promulgated the German Civil Code, which made some adjustments compared with the French Civil Code in terms of contract legal system and became another symbol of modern contract law in civil law countries. Judging from the content and historical development of contracts in French Civil Code and German Civil Code, modern contract law mainly has the following basic principles: the principle of freedom of contract; Principle of good faith; The principle of fair dealing.
One is the principle of freedom of contract, which has three meanings in modern times: equality of parties; The parties are willing; The parties are free to move. After the publication of the Declaration of Human Rights, equality of all people has become the constitutional principle of the bourgeoisie, and equality of all parties is self-evident. Therefore, the freedom of contract in contract law is mainly aimed at the voluntary will and freedom of action of the parties. Article11kloc-0/of the French Civil Code stipulates: "A contract is an agreement whereby one or more people assume the debts of payment, action and omission to others." Article 154 of the German Civil Code stipulates: "Everything must be agreed. If both parties fail to reach an agreement on all the key points in the contract, the contract shall be deemed invalid in case of doubt. " These provisions fully reflect the will and freedom of action of the parties, thus laying the cornerstone of the principle of freedom of contract [1][ 1].
Second, the principle of good faith. As a legal term, the principle of good faith originated in ancient Rome and has been preserved in modern civil law. Article 1 134 of the French Civil Code stipulates: "A contract established according to law has the same legal effect among the parties to the contract", "The contract mentioned in the preceding paragraph shall be performed in good faith", and Article 157 of the German Civil Code stipulates: "Interpretation of the contract.
Third, the principle of fairness. In social life, the bargaining power is different because of the unequal information possession and funds of all parties. If the machinery requires equality and voluntariness, the transaction will be difficult to complete or the transaction cost will increase greatly. Therefore, in practice, equality and voluntariness are not absolute requirements. As a supplement, contract fairness is emphasized. The format contract is a typical example. Generally, the standard contract is strictly examined and explained in accordance with the public plain rules. For example, in Germany, the common conditions there cannot properly arrange the interests of both sides according to the principle of good faith.
Almost at the same time that modern contract law was formed in civil law countries, common law countries also laid the foundation of modern contract law through court precedents and statutory laws, and its basic principles are similar to those in civil law countries.
The first is the principle of freedom of contract. Modern contract law in Britain and America originated from Britain in the19th century, which was the golden age of the development of free capitalism, and the theory of free competition was dominant in the economy. In the legal aspect, Main's Ancient Law reveals the development trend from identity to contract, and under this background, contract liberalism has been strengthened unprecedentedly. Earl George Jessel, a famous British judge, said in the case of printing and digital registration company v. sampson: "If there is one thing that is more important than another thing required by public order, it is that adults and people with sound minds should have the fullest freedom to conclude contracts. If the contract they signed is free or voluntary, then they should be regarded as sacred and should be enforced by the court "[2][2]. In the United States, both the Declaration of Independence and the 1787 Constitution regard civil liberties as an important object of legal protection.
The second is the principle of good faith. Anglo-American law holds that honesty is the way to treat the parties to a contract honestly and fairly. In Britain, in the early days, equity mainly dealt with contract cases involving fraud, and the principle of good faith was established in these cases [3][3]. In the United States, the promulgation of Uniform Commercial Code clearly confirmed the principle of good faith. Article 1-203 of the Code stipulates that all contracts and obligations involved in this law have the obligation to follow the principle of good faith when performing and executing. Of course, specific to the case, the understanding of the principle of good faith is still different. For example, in a hypothetical case, a geologist inspected a piece of land and found a property with great development value, so he bought the property without telling the truth. Opinions vary as to whether it violates the principle of good faith. Coleman thinks no, and Farnsworth thinks it violates [4].
The third is the principle of fairness. There is an unfair profit system in equity. If one party is allowed to have an interest, which is obviously unfair, then the other party will be allowed to take back the interest. Whether the victim has a reasonable opportunity to avoid such improper behavior is an important factor to be considered when deciding whether it constitutes improper profit. In terms of standard contracts, American law authorizes judges to refuse to execute contracts that he considers "unfair".
Freedom of contract, good faith and fairness are the basic principles of contract law, which is indisputable, but there are three problems: first, the definition of these three principles is very abstract, and if they are applied to specific cases, their connotation and scope of application need to be further clarified; The second is how to understand the internal relations of these three principles; Third, why they become the basic principles of contract law. Using the research methods of law and economics can answer the above questions.