While reading the text, this Rosetta Stone commercial came to mind when talking about Appeal to Authorities. Authorities are only authorities in their field of expertise. A doctor is qualified to make medical statements, a Lawyer is qualified to make legal statements, and an olimpic swimmer is qualified to make statements about swimming, however, none are qualified to make a statement saying one washer machine is better than another.
Olympic gold medalist, Michael Phelps, is an expert at swimming and is fully qualified to make statements about swimming. However, Phelps is not qualified to make statements about learning a new language and it is fallacy of appeal to authority. In the text, Logic and Contemporary Rhetoric, this example falls under “Authorities in One Field Aren’t Necessarily Experts in Another” where it discusses how athletes are experts in their sport but know nothing more about things outside of their field of expertise than anyone else. Using Michael Phelps to promote Rosetta Stone, does not give any validity to Rosetta Stone as a product because Phelps is not qualified to statements about their product. In many commercials they use athletes, actors, and other famous people to promote products that they do not have any more qualifications than you or I in the field.