Or is an immoral or wicked promise not a real “promise” qua promise at all? In either case, we need to have some reliable method of determining right from wrong, yet most (if not all) theories of promissory obligation fail to distinguish between morally ‘good’ and morally ‘bad’ promises in any systematic manner. Even consequentialist theories are deficient in this regard, since utilitarians are no better at predicting the probabilistic consequences of promise-keeping or promise-breaking than the rest of us are. (Update: we have posted a revised draft of our most recent paper Immoral Promises on SSRN. Our paper was previously titled “illegal promises,” but we have decided (for now) to focus on promises that are malum in se or inherently wrong or wicked.)