1 Corbin on Contracts § 1.19

Summary

Contractual duty is imposed by reason of a promissory expression. As to this, there is no difference between an express contract and an implied contract. All contracts are express contracts, subject to the rules of contract law. Thus, where a party is incompetent1 to make an express contract or lacks the authority to bind the principal, such incompetency or lack of authority2 is equally fatal to any theory of an implied in fact contract.3