Describe the main rules applying to the doctrine of consideration ?

1. Consideration must be something of value: Consideration must be something of value exchanged between the parties involved in a contract. It can be money, goods, services, promises, or anything else that has value.

2. Consideration must be bargained for: Consideration must be the result of a bargain between the parties. It cannot be something given as a gift or donation.

3. Consideration must be given by both parties: Both parties involved in the contract must give consideration in order for the contract to be valid. One-sided promises or gifts are not considered valid consideration.

4. Consideration must be legal: The consideration exchanged between the parties must be legal. It cannot involve illegal activities or go against public policy.

5. Consideration must be sufficient but need not be adequate: Consideration must be sufficient, meaning it must have some value, but it does not need to be equal in value to what is being exchanged. As long as there is some value exchanged, the consideration is considered valid.

6. Past consideration is not valid: Consideration must be given in exchange for the promise or action of the other party. Past consideration, meaning something that was done before the contract was formed, is not considered valid consideration.

7. Consideration must be real: Consideration must be real and not illusory. It must involve a real exchange of value between the parties. Promises that are too vague or uncertain are not considered valid consideration.

Main Rules Applying to the Doctrine of Consideration

1. Consideration Must Be Bargained For:
- Consideration must be something of value given or promised in exchange for the promised performance.
- It must be provided by the promisee or a third party at the request of the promisee.

2. Consideration Must Be Sufficient:
- While consideration does not need to be equal in value to the promise, it must be of some legal value.
- Courts will not enforce contracts where consideration is nominal or illusory.

3. Consideration Must Be Legal:
- Consideration cannot be illegal, immoral, or contrary to public policy.
- Contracts based on illegal consideration are void.

4. Consideration Must Be Pre-existing or Simultaneous:
- Consideration must be present in the contract at the time the promise is made.
- Past consideration (something already performed) is generally not sufficient unless it was specifically promised in advance.

5. Consideration Must Be Definite:
- The nature and value of consideration must be clear and certain.
- Indefinite or speculative consideration is not enforceable.

6. Consideration Must Move from the Promisee:
- The promisee must have provided the consideration, or it must have been provided by a third party at the request of the promisee.

7. Past Consideration Doctrine:
- In certain exceptional circumstances, past consideration may be sufficient if the following conditions are met:
- The past consideration was not requested by the promisor.
- The promisor subsequently expressly or impliedly promised to pay for it.

Exceptions to the Doctrine of Consideration:

- Promissory Estoppel: Estoppel may prevent a party from denying the existence of consideration if they have induced another party to rely on a promise to their detriment.
- Charitable Subscriptions: Promises to donate to charitable organizations may be enforceable without consideration due to the public benefit involved.
- Unilateral Contracts: Offers that invite unilateral acceptance through performance may create binding contracts even without express consideration.