"The Other Two" is a comedy of manners about husbands and a wife and adjustments to society. Edith Wharton has explored marital themes in other short stories, but some critics believe this story to be Wharton's most nearly perfect short story in structure and substance. Other critics consider Wharton's stories colorless unengaging imitations of Henry James' stories. In "The Other Two" Wharton explores the contrasting ideas of illusion and belief as well as the related idea of ethics.
In the story, Waythorn is under the illusion that his wife behaves with disinterestedness toward her two ex-husbands, one of whom comes to the Waythorn home to attend to the ill daughter he shares with his ex-wife who is now Waythorn's wife and one of whom the Waythorn's meet in social settings. In this scenario, Mrs. Waythorn creates the illusion, through withholding information, that she is behaving with disinterest toward her ex-husbands, leading Waythorn to the belief that her deportment is above questioning.
Once the illusion is shattered and the belief discarded, the question of ethics remains: What is the ethical thing to do when one has three husbands (two of them ex-husbands) who are thrown together by circumstances? Mrs. Waythorn decides that it is ethical to only speak to them in social gatherings when directly approached by one--and she decides to serve them tea. Supposedly, her current husband agrees with this ethic because he sees the humor of having two of his wife's former husbands in his parlor drinking tea with him.
Thus the significance of "The Other Two" is that it examines the social mores and values of the times by examining an awkward but increasingly common situation in which spouses have multiple spousal connections, thereby exposing the nature of illusion, belief and ethics.