What can be something of value, or it can be promising to do something not required by law or promising to refrain from doing something permitted by…

The question describes the legal concept of "consideration," which is a fundamental element required for a contract to be enforceable. Consideration is the bargained-for exchange of something of legal value between the parties. This value can be an affirmative act (doing something one is not legally obligated to do), a forbearance (refraining from exercising a legal right), or a promise to do either. It is essentially the "price" each party pays for the other's promise or performance, ensuring that the contract is a two-way street and not a one-sided, gratuitous promise.

A. Irrevocability: This refers to a state where an offer or action cannot be withdrawn or cancelled; it is not the value exchanged.

B. Acceptance: This is the offeree's unconditional agreement to the terms of an offer, which is a separate element of contract formation.

D. Conclusiveness: This pertains to the final and binding nature of a decision or evidence, not the exchange of value in a contract.

1. National Contract Management Association (NCMA). Contract Management Body of Knowledge (CMBOK), 6th ed., 2019. In section 1.2.1, "Essential Elements of a Contract," consideration is defined as "the cause, motive, price, or impelling influence that induces a contracting party to enter into a contract." It further explains that consideration must be a bargained-for exchange involving a legal detriment to the promisee or a legal benefit to the promisor.

2. Cornell Law School Legal Information Institute (LII). "Consideration." Wex Legal Dictionary/Encyclopedia. Accessed 2023. The LII defines consideration as "Something of value given by both parties to a contract that induces them to enter into the agreement to exchange mutual performances." It clarifies that this can be a promise, performance, or forbearance.

3. Garrett, G. A. World-Class Contracting, 6th ed., CCH, a Wolters Kluwer business, 2016. In Chapter 3, "Contract Law," the text explains that for a promise to be enforceable, it must be supported by consideration, which is defined as "a bargained-for exchange of a legal detriment between the contracting parties." This detriment can be doing something one is not obligated to do or refraining from doing something one has a right to do.