Final answer:
David McClean in the story acts as a foil character, providing contrast to the main character and serving to highlight particular traits. He might also have elements of a mentor figure, guiding other characters, but he is not an antagonist or merely symbolic.
Step-by-step explanation:
The character of David McClean in the story serves as a foil character. A foil is a character who provides contrast to the main character (protagonist), often highlighting their traits or playing a pivotal role in the story's conflict. In the context of the story, McClean emphasizes certain qualities of the main characters by being their polar opposite. They might represent the rational or logical contrast to the more emotionally driven protagonist or serve to illuminate where the protagonist is lacking in certain areas such as decisiveness or moral clarity. From these interactions, the reader gains deeper insights into the protagonist's character.
As a psychologist in the story, McClean could also be seen as approaching the role of a mentor, given that psychologists often guide and advise their patients. However, without more specific context from the story in question, it's difficult to decisively categorize his role as purely that of a mentor. It is essential to carefully analyze McClean's interactions with the other characters, his development in the story, and the thematic elements the author is exploring to discern McClean's full role. His inclusion would not be that of an antagonist, as he does not oppose the protagonist directly, nor is he simply a symbolic figure, as he plays an active role in the unfolding events.