 Despite its theoretical and moral purity, the anti-supererogationist view is open to criticism. The good-ought tie-up rests on an ambiguity in the concept of ought, which may be interpreted either in a commendatory sense or in a prescriptive sense. “You ought to see the current Caravaggio exhibition” provides one with a reason for action, an advice, a recommendation that is not binding. “You ought to attend the next faculty meeting” may be a conclusive reason for action, a prescription. To further complicate matters, “ought” is often used impersonally, as in “it ought to be nice weather for our picnic tomorrow,” but also personally, as in “you ought to buy wine for the picnic.” And “the picnic ought to have been better organized” lies between the personal and the impersonal senses of “ought,” referring to some unspecified agent without addressing a prescription to any particular individual.