在美国合同法下，形成一个合同需要Mutual Assent（双方合意）和Consideration（对价）。双方的合意是通过Offer and Acceptance（要约与承诺）来实现。

 

简而言之，一份有效的合同应包括offer，acceptance，consideration三个要素。

 

Formation of Contract

Mutual Assent

1. Offer

Restatement § 24. Offer Defined

An offer is the manifestation of willingness to enter into a bargain, so made as to justify another person in understanding that his assent to that bargain is invited and will conclude it.

2. Acceptance

Restatement § 50.  Acceptance of Offer Defined;

(1) Acceptance of an offer is a manifestation of assent to the terms thereof made by the offeree in a manner invited or required by the offer.

3. Consideration

In the legal system, the term consideration in contract law refers to something of value given to someone in return for goods, services, or some other promise. A valid contract must include consideration for every party involved. In simple terms, consideration is the basic reason a party enters into a legal contract. 

 

 

01

Offer 要约

美国《合同法重述》 (第二次)第24条规定，要约是“订立合同的意思表示，它使得另一个人有理由认为，此方邀请其同意该合同，并且合同因为其同意而成立”。

要约没有形式上的要求，它不是必须要由文字来表示。要约既可以用“要约”（offer）这一言辞明确地表示，也可以通过要约人的语言暗示出来，甚至可以通过要约人的行为表示出来。

通常，要约是由以下三个方面构成的: 

(1)必须明确表示有创设一个受法律约束的义务的意图；

(2)要约的基本内容必须确定，基本内容包括订约对象、标的、价款、履行期限或履行方式；

(3)要约必须送达，但并不要求要约人直接向受要约人传达。

02

Acceptance 承诺

承诺(acceptance)是受要约人对要约的接受或同意。

承诺有两层含义: (1)对要约人提议的接受；(2)对要约人要求的允诺，或者完成了被要求的行为。

美国《合同法重述》 (第二次)第50条第1款对承诺作出了定义: “承诺就是受要约人依照要约所邀请或要求的方式，对要约人表示接受其要约而成立合同之意思表示。”

通常情况下，受要约人的承诺必须明确地表示出来，这种表示可以是以文字的形式，也可以通过受要约人的行为表示。

对于表示承诺的方式，普通法（Common Law）的一般原则是，承诺必须无条件地和绝对地同要约的内容相一致，受要约人必须无条件地同意要约的全部内容，不能对要约作出任何保留、修改或者增减。这就是所谓的“镜像规则”(Mirror Image Rule)。

但是，《统一商法典》（UCC）对表示承诺的方式，采取的更为宽松的“格式之战原则”（Battle of the Forms），即在商品买卖中，如果一方当事人以另一种形式作出承诺，即使与要约中的内容不一致，但是在某些情况下整个合同或合同中的部分内容也可能是有效的。具体需要再考虑要约人和受要约人的身份、以及冲突内容对于合同来说是否是关键的等因素。

03

Consideration 对价

对价是合同成立的诱因。换言之，许诺人（promisor）为了获得对价而作出许诺，受诺人(promisee)为了得到承诺人的许诺而提供对价。因此，对价与诺言（promise）互为交易对象。

英美法中对价制度十分抽象，不过经过长期的发展，法院对consideration的判断主要有两种标准:

(1) Benefit-Detriment Approach（获益一受损标准）。受诺人承诺或者履行了其在法律上原本无义务的作为或者不作为， 即受诺人受到“损害”（detriment）。

这样的对价，可能是当事人一方所得之权利、利益、利润或者获利，或者是另一方当事人因克制自己所受的不作为、不利益、损失或者义务(责任) 。

(2) Bargained-for Exchange（交易理论）。许诺人为了获得对价而作出许诺，受诺人为了得到诺言人的许诺而提供对价，因此 对价与诺言互为交易对象（bargained-for exchange）。

 

LEC真题演练：

 

1. Melonie had been working with an accounting firm for three years. Although the work was busy, she was paid quite well. After she had her first baby, she hired a nanny to help take care of her child. Her mother-in-law, Melinda, disapproved the nanny and tried to persuade Melonie to quit her job and take care of the baby herself. One night, Melinda came to visit and said to Melonie: "If you quit your job and take care of the baby by yourself for three years, I promise I will give you $2,500 each month as a compensation for your sacrifice".

Melonie discussed with her husband Henry, and they thought it would be a great idea. The following Monday, Melonie resigned from her firm, fired the nanny, and started to stay home taking care of the family. However, Melinda never gave her any money.

If Melonie sues Melinda for breach of contract, which of the following defenses claimed by Melinda would be accepted by the court?

A.There was no offer.

B.There was no acceptance since Melonie did not make a promise to Melinda.

C.There was no consideration because no legal value exchanged.

D.None of the above.

 

2. Melonie had been working with an accounting firm for three years. Although the work was busy, she was paid quite well. After she had her first baby, she hired a nanny to help take care of her child. Her mother-in-law, Melinda, disapproved the nanny and tried to persuade Melonie to quit her job and take care of the baby herself. One night, Melinda came to visit and said to Melonie: "If you quit your job and take care of the baby by yourself for three years, I promise I will give you $2,500 each month as a compensation for your sacrifice".

Melonie discussed with her husband Henry, and they made a decision. The following Monday, Melonie talked to her boss and switched to a part-time position so that she would only need to work 20 hours each week. After she told Melinda what she did, Melinda never responded and never paid her anything. So Melanie decided to sue Melinda for the $2,500 monthly payment. Which of the following statements is true?

 

A. Melanie could not get compensation because there was no contract.

B. Melanie could not get compensation because there was no consideration.

C. Melanie could not get compensation because Melinda did not have income.

D. Melanie could only get $1,250 as compensation.

 

参考答案见底部~

 

参考答案为：1. B 2. A

 

(文章来源：法平教育)