 I shall further observe, that, since every new promise imposes a new obligation of morality on the person who promises, and since this new obligation arises from his will; it is one of the most mysterious and incomprehensible operations that can possibly be imagined, and may even be compared to transubstantiation or holy orders, where a certain form of words, along with a certain intention, changes entirely the nature of an external object, and even of a human creature. (Treatise, 3.2.5; emphasis in the original)