‘The fictionable world’ is a phrase from Finnegans Wake, and the pun is obvious. Joyce is thinking of the fashionable world, and putting himself at some distance from it. But the idea that a world could be fictionable, as a slander or an insult, say, may be actionable, does perhaps have some force to it. There would, for the word to make sense, have to be worlds which are not fictionable, and we could wonder what they are. And then fictionable wouldn't mean quite the same as fictional, or fictitious. It would mean available for conversion into fiction; ripe or ready for fiction, or at least not intrinsically resistant to it. A fictionable world would perhaps catch fiction's eye; fiction would find it promising. Fiction might even start a fashion.

This chapter falls into two parts: one about a string of reactions to the story of Nietzsche's lapse into madness, and one about a recent novel which revisits the scene of that madness. The underlying question in both cases is what Nietzsche called ‘le gai savoir’, or ‘la gaya scienza’ – the title of his famous book is Die Fröhliche Wissenschaft, ordinarily translated as The Gay Science. Bernard Williams's introduction to a recent English-language edition glosses this phrase gracefully and amply: