joyce
Explanation
The Joke
The comic shows a futuristic-looking person (possibly a cyborg, given the mechanical goggle-like eyes) in the year 2358, reading a book. The caption explains this is "January 1, 2358: the first person to reach the middle of James Joyce''s Finnegans Wake makes a startling discovery." The reader exclaims: "Oh my GOD. It''s a photo of him laughing and mooning the reader. Has this been here the whole time?!"
The joke imagines that James Joyce deliberately hid a photograph of himself laughing and exposing his backside in the exact center of Finnegans Wake, knowing that the book is so infamously difficult and impenetrable that it would take over 400 years (from its 1939 publication) before anyone actually made it to the middle. The implication is that Joyce wrote the entire book as an elaborate prank -- the incomprehensible prose was never meant to be deep literature, but rather a smokescreen to conceal the ultimate literary trolling.
The Humor
The humor works on multiple levels. First, it satirizes the extreme difficulty of Finnegans Wake, which is written in a dense, multilingual, stream-of-consciousness style that even dedicated scholars find nearly impenetrable. The idea that it would take until the year 2358 for anyone to reach the middle is a hyperbolic but affectionate jab at just how challenging the book is. Second, it plays on the longstanding suspicion that some notoriously difficult literary works might be more about the author showing off or pranking readers than actually communicating something meaningful. The idea that Joyce was secretly just "mooning the reader" is a comedic literalization of that suspicion.
The futuristic setting with the cyborg-like reader adds to the joke -- even with centuries of technological advancement, Finnegans Wake remains an almost insurmountable challenge.
References
"Finnegans Wake" (1939) is the final novel by Irish author James Joyce. It is written in an idiosyncratic language composed of composite words drawn from dozens of languages, portmanteau constructions, and dense allusions. It is widely considered one of the most difficult works in the English language. Literary scholars have debated for decades whether its obscurity reflects profound artistic vision or deliberate obfuscation, making it a perfect target for this kind of joke.