Reliance in the Revised "Restatement": The Proliferation of Promissory Estoppel

The original Restatement of Contracts' stated three requirements for the formation of a contract: a promisor and promisee each with legal capacity, a manifestation of assent, and sufficient consideration.2 Following its detailed treatment of these conventional elements of the ordinary contract,3 the Restatement presented a group of sections dealing with "Informal Contracts Without Assent or Consideration." Most of these "informal contracts" involved later promises to perform obligations that originally arose out of transactions in which assent and consideration had played a part, but that (for a variety of reasons) had become unenforceable;5 thus they did not represent exceptions to the general proposition that promissory liability depends on both mutual assent and an underlying exchange of consideration. In section 90, however, the Restatement did present such a clear-cut exception. In a mere six lines of black-letter text, section 90 called for the enforcement of a different kind of promise: a "Promise Reasonably Inducing Definite and Substantial Action." 6 The original section 90 had no supporting comments; it was followed by four illustrations, of three promises that were enforceable under section 907 and one that was not.8