Question
Psychologist: The obligation to express gratitude cannot be fulfilled anonymously. However much society may have changed over the centuries, human psychology is still driven primarily by personal interaction. Thus, the important social function of positively reinforcing those behaviors that have beneficial consequences for others can be served only if the benefactor knows the source of the gratitude. Which one of the following most accurately describes the role played in the psychologist’s argument by the claim that the obligation to express gratitude cannot be fulfilled anonymously?