Mulligan engages in a little smack-talking before diving in the water. Self-consciously or boastfully, he stands naked before jumping in and shows off his Nietzsche, and though he’s joking, he’s also revealing his not-so-secret desire to be linked with Stephen as a superman, as the architect of a new age.
One of the great things about seeing this chapter in the comic form is the way it makes obvious visual elements of the scene. Like Mulligan’s nakedness. When you read the chapter, you know that he’s taken off his clothes and is going to be swimming naked, and on some level you know that as he talks about himself as the Ubermensch, that he’s naked… but seeing it illustrated is another thing entirely.
What does it say about Mulligan? It would have been perfectly ordinary for a man to swim naked at the Forty Foot on a warm June day in 1904, but Mulligan needs to make a show out of it. He ain’t shy. And he also wants to be seen by those around him as being connected to Stephen.
I suppose there’s more I could say about Mulligan’s reference to Nietzsche–just Google “Nietzsche and Joyce” and you get a whole cascade of articles and books. [Here’s one of some interest.] But I’m leery of going too far down the rabbit hole of references and annotations. Suffice it to say that there was a considerable intellectual fad for his writings across Europe in the early 20th century, and that Mulligan’s reference shows him to be attuned to that fad. It’s also true that Oliver St. John Gogarty, on whom the character of Mulligan is based, was reading the German philosopher at this time.