Pritchett's story is about the enormous if unspoken gap between a father nearing the end of his life and his adult son, whose professional career has failed to meet the elder's expectations. Or perhaps the father's expectations for the son had always been so limited that the former's disdain for the latter's professional shortcomings provides the moral ammunition the father requires to continue to berate the son. In either case, Pritchett's protagonist, the son, arrives at his father's business on the day the doors to that business will close forever. This, the son thinks, might provide the basis for the development of a new relationship between father and son, as the father's bankruptcy will certainly humble him sufficiently to allow for a more balanced adult relationship. As the son notes to himself early in the story, “Thirty years of your life come to an end. I must see him. I must help him.” The child is becoming the caregiver for the aging parent -- the great equalizer in family histories. What Pritchett's story is about, however, is the son's realization that the father has not and will not change the way he views his son. The condescending attitude and open displays of contempt will not cease to exist just because the father has failed in his professional endeavors.
"The fly in the ointment" is an old phrase used to note the slight flaw in an otherwise admirable plan. In the context of Pritchett's story, is used to suggest the fatal flaw in the son's idealized version of the relationship he will enjoy in the future with a father who has previously exhibited little use for him. As noted, the story takes place on the last day of the father's business. The doors are shuttered, the equipment turned off, the phones are silent. The old man is left with only the walls that surround him and, now, with the visit by his son. The following passage from the story illuminates the vacuum that has now emerged in the father's vision:
“There’s a fly in this room,” said the old man suddenly, looking up in the air and getting to his feet. “I’m sorry to interrupt what you were saying, but I can hear a fly. I must get it out.”
“A fly?” said his son listening.
“Yes, can’t you hear it? It’s peculiar how you can hear everything now the machines have stopped. It took me quite a time to get used to the silence."
The fly in the room is a metaphor for the dysfunctional relationship that now fills the room. It could also, to apply another commonly used metaphor, be the "elephant in the room." It is the unspoken but very prevalent flaw in the arrangement. The son views his father's struggles to defeat the fly as almost symbolic of the shift in power that may have occurred now that the old man's failures are so evident. The following passage emphasizes the increasing frailty of the father and the natural tendency for the son to try to assume the metaphorical weight of the relationship:
“Be careful,” said the son. “Don’t lose your balance.”
The old man looked down. Suddenly he looked tired and old, his body began to sag and a look of weakness came on to his face. “Give me a hand, old boy,” the old man said in a shaky voice. He put a heavy hand on his son’s shoulder and the son felt the great helpless weight of his father’s body.
“Lean on me.” Very heavily and slowly the old man got cautiously down from the table to the chair.
The son views this experience with the father's efforts at killing the fly and his physical need for his son's assistance as the transitional moment for which he hopes. Alas, the father succeeds merely in illuminating the flaw in his relationship with his son. As the two continue their conversation, the son realizes that his father is incapable of change. The benevolent approach the old man adopts for strangers is but a facade he uses for pecuniary purposes. Beneath that exterior is a conniving, resentful, and distasteful human being. His inability to change is the fly in the ointment.