Testimonial knowledge through unsafe testimony

Frank is a writer with a strange habit. Every morning, at precisely 7:30 a.m., he wakes up and dumps out whatever is left of the pint of milk he purchased the day before, but places the empty carton back in the fridge until noon. Then, throughout the interval from 7:30 to noon, he always remains in the kitchen, as that is where he writes every morning like clockwork. Finally, at exactly noon, he takes the now-empty milk carton out of the fridge and throws it away – an act which to him symbolizes the end of his day’s writing. Now Mary is unaware of Frank’s milkdumping practice. One morning, having spent the prior evening at Frank’s house with Frank and her son Sonny, she awakens at 7:40 and goes to the kitchen with Sonny. Upon entering (Frank is already there) she immediately goes to the fridge for a glass of OJ, and as she reaches for the OJ she casually observes a small carton of milk. She goes on to tell Sonny (who always has cereal with milk for breakfast) that there is milk in the fridge. As luck would have it, there is indeed milk in the carton on this day (Frank failed to remember that he had bought milk yesterday). When Frank observes Mary’s testimony, he realizes that he forgot to dump the milk; when Sonny observes her testimony, he forms the belief that there is milk in the fridge. In what follows I want to argue that the following two claims hold: