Okla. Stat. tit. 15 § 2 : Contracts — Nature of Contracts —Definition and Essential Elements — Essential Elements of Contract

It is essential to the existence of a contract that there should be:

1. Parties capable of contracting.
2. Their consent.
3. A lawful object; and,
4. Sufficient cause or consideration.

Okla. Stat. tit. 15, § 2

R.L. 1910, § 876.
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