In her recent article, “The One Necessary Condition for a Business Ethics Course: The Teacher Must be a Philosopher,” Ellen Klein argues that philosophers are best qualified to teach business ethics by virtue of their expertise in ethical theory. Klein likens her claim to that of Plato’s “philosopher-king,” who claimed that the philosopher is best suited to be “king,” because he possesses a theoretical understanding of justice. In response to Klein, I point to Aristotle’s objection to Plato, which shows that theoretical knowledge of ethics is not sufficient for making a person ethical, because ethics requires both theoretical and practical knowledge. Ultimately, I argue that in order to have a successful business ethics class, one must address both the issues unique to ethical theory, and the particular structures and contexts that are unique to making an ethical decision within the business environment.