Sitting there he could not have meant to avoid it. There's a title. An essay on dialogue. After all, it's not a popular form any longer. On the contrary.
Dialogue is everywhere.
Though I don't know if I'd call the loose give and take of most drunken barroom chat dialogue. Nuggets can be found there too, I would imagine. Currently I am considering the dialogue specifically as a literary device. I thought that went out with the Greeks. The dialogue has always been a popular form of presentation, preferred over the essay in many cases.