Without the basis for such special expectations, the act utilitarian's promise fails to function as a genuine promise.

Note that the utilitarian cannot reply that we have failed to take into account the expectations of the promisee in our case, because the claim is that the promisee has no reason to generate any special expectations that the promisor will do what she promises, precisely because he knows the promisor to be an act utilitarian, and consequently knows that she will do what the utility calculus tells her is best, without thought of her promise. Of course, the promisee is free to generate some expecta