The dean of a university is searching for a new chair for his chemistry department. He offers the job to one candidate, who says she’ll accept only if she can hire three new faculty members. The dean makes a commitment to support these hires.

Such arrangements are common, but that’s troubling: By making a promise, the dean has made a future act obligatory for himself, and that changes its moral status. What if the promised act would otherwise have been wrong? In this case, what if the funding for these three hires ought otherwise properly to have gone to another department?

“The fact that our moral system permits agents to dictate in this manner the moral status of their future actions seems an astonishing power to build into a moral system,” writes University of Arizona philosopher Holly M. Smith. “It is especially troubling when one notes that agents apparently can exploit promises in order to legitimize otherwise objectionable courses of action. What would we say, for example, about a moral system in which an agent may render A obligatory by simply declaring, ‘My doing A next week will be, by virtue of this declaration, morally obligatory’?”

(Holly M. Smith, “A Paradox of Promising,” Philosophical Review 106:2 [April 1997], 153-196.)