In simple terms, the statement suggests that forgetting someone can be an effortless task if a person decides to do so. The speaker believes they have managed to forget about their poor uncle as if he never existed, and they see this act of erasure as their duty.
Beyond its surface meaning, this quote delves into the complexities of human memory and conscience. It highlights how people can suppress painful or uncomfortable memories by making a conscious effort to detach themselves from them emotionally. This process might be seen as fulfilling a moral obligation if forgetting serves to bring emotional relief or closure. However, it also raises questions about the nature of responsibility and whether neglecting past relationships, even for personal peace, is truly virtuous.
The quote comes from Richard Brinsley Sheridan, an influential Irish playwright and politician active during the late 18th century in England. Known primarily for his wit and satirical works, Sheridan was a prominent figure in London's cultural scene and contributed significantly to the development of English drama with plays like "The School for Scandal" and "The Rivals."