Uh, maybe he was just being funny …

… Groucho Marx: The Comedy of Existence by Lee Siegel, reviewed. ( Hat tip, David Tothero.)

When Groucho first encounters Harpo in Duck Soup, he asks him who he is, and Harpo answers by rolling up his sleeve and revealing a tattooed image of his own face. This answer transforms Groucho’s social request for an introduction into a fundamental philosophical question: Can we ever pinpoint a person’s true identity? It also asks an even more fundamental question about representation in language: How can we point to something in the world with complete accuracy, without also being meaninglessly redundant? Harpo’s answer to “who are you?” is a visual-gag version of the Buddha’s infuriatingly honest answer to the same question. When asked  who he was, he would say, gesturing to himself: I am thathagatha (the one who is like this).

Nothing kills a joke faster than po faced commentary.