The common law of contract famously enforces the outward manifestation of agreement rather than the parties' inner states of mind. Under this objective theory, a promisor is bound not by what he privately intended but by what a reasonable person in the promisee's position would have understood his words and conduct to mean. The doctrine is often defended on frankly practical grounds: subjective intent is hidden and easily fabricated, whereas outward expression is observable and can be tested by evidence. A regime that policed secret intentions would, it is said, make every contract hostage to self-serving testimony and would deter the reliance that commerce requires. This justification, though sound as far as it goes, is incomplete, and its incompleteness has consequences that courts do not always acknowledge. The objective theory is not, in fact, indifferent to intention; it is indifferent only to intention that has not been communicated. What the reasonable-person standard protects is the promisee who has justifiably relied on an appearance the promisor created. Where no such reliance exists - where the promisee knew, or had reason to know, that the promisor's words did not reflect his actual meaning - the rationale for holding the promisor to the objective appearance evaporates, and the law duly declines to do so. The familiar rule that a promisee cannot snap up an offer he knows to be the product of a clerical error is not an exception to the objective theory but an application of its underlying logic. The standard is objective, but it is the objectivity of a particular observer situated in a particular transaction, not the objectivity of a detached spectator indifferent to what the parties knew. This point is frequently obscured by the theory's own rhetoric. Judges who speak of enforcing the reasonable meaning of the words as though meaning inhered in the words themselves invite the error of treating the standard as a mechanical one, to be applied without inquiry into the promisee's actual knowledge. The result is a species of formalism that the objective theory, correctly understood, does not require and cannot justify. A promisor who has misspoken, and whose error is apparent to the party he addresses, is on the theory's own premises no more bound than one whose intent was correctly conveyed. None of this is to deny the theory's central insight. The alternative - a subjective theory that made the existence of a contract depend on a concurrence of inner wills - would indeed be unworkable, and the objective standard's refusal to excuse a party merely because he later claims to have meant something else is essential to the security of transactions. The point is rather that the standard's justification and its content are more closely bound than the practical defense suggests. Because the theory exists to protect justified reliance, its reach is limited by the conditions under which reliance is justified. A court that enforces an objective appearance no one was entitled to rely upon has not applied the objective theory too rigorously; it has misunderstood what the theory is for.