I can exclusively reveal the title of Umberto's Eco's next novel. It will be called The Last Night of Napoleon. Or Copericu's Lover. Or perhaps The Fall of Oscar Wilde's House. Or then again maybe The Soul of Animals Revisited.

The nimble-thinking Italian novelist and professor of semiotics writes these alternatives on a small piece of paper he suddenly magics out of a pocket at the end of our lunch together at J. Sheekey, the fish restaurant in Covent Garden. The venue was my choice - a good one in terms of food and people-watching, but a disaster for an interview because of the deafening clatter-and-bray of fashionable lunching at small tables a few feet apart. Only our solo neighbour on the plush corner banquette is quiet: it is Michael Grade, executive chairman of ITV, waiting for his date. He tunes in to our conversation with an amused smile - and a glance of sympathy at me. He knows that deciphering my tape recording will be an ear-splitting experience.

Thank goodness for paper. Among the titles Eco wrote down, devotees of his work will spot references to some favourite themes (he once said that Oscar Wilde deserved to go to prison for the appalling prose in his love letters), and will not be surprised that he adds lightly that it is of course a tease, ''a little ox''. (An ox? I have a moment of wild confusion before the light dawns. Eco's English is highly expressive but strongly accented: he means a hoax.)

Oxes, puzzles, teases, unreliable narrations and intellectual labyrinths have been a feature of Eco's fiction since the success of The Name of the Rose transformed his life in 1980. His second novel, Foucault's Pendulum of 1988, outlined the entire plot of The Da Vinci Code in a few paragraphs; Borges and James Joyce are among his literary pantheon. But this little wordgame is an act of kindness. When we meet, Eco has just flown in to London after an exhausting five days in New York: he is tired and jetlagged, he is not well, he is worried that he isn't giving me enough for our interview.

There will be nothing to write in the menu box on this page, he says as we sit down - he has no appetite. So he will just have a lobster. (He has glanced at the menu for a matter of seconds.) Could he have it, he asks the maitre d', cooked with no oil or butter? Impossible, comes the dignified reply: it would burn. Garlic? There follows a brief comedy of miscomprehension that would easily be solved if they spoke to each other in the native tongue they clearly have in common; they don't. Water comes, and Eco says he will have a large whisky (doctor's orders: there is no sugar in whisky).

Stocky and bearded, he looks like a man whose doctor would tell him off a lot - and who would take little notice. I remember fleetingly that this multi-minded 75-year-old has been dubbed a bon viveur in the intellectual department, too - but decide that this may be an unworthy way to refer to his enormous and varied output: more than 40 books to his credit, including academic works on semiotics, philosophy and literary criticism, as well as novels, essays and journalism.

The two books that Umberto Eco has published this autumn exemplify the range. One is Turning Back the Clock: Hot Wars and Media Populism, a collection of the essays that make Eco the very model of the European ''public intellectual'', who ranges from high to low culture with ease and addresses his audience across the modern media. The other is an illustrated compendium entitled On Ugliness, a companion volume to 2004's On Beauty. Its illustrations of monsters and grotesques, massacres and mutilations are lavish: I suggest that it's actually a sumptuously beautiful book on ugliness.

''Yes, and to make a book like that is more amusing than to make a book on beauty, because beauty is boring. Beauty is boring because it is predictable. Even looking for the images to include was more interesting - you had to look at the margins of paintings, and the margins of the tradition.''

Beauty has been out of fashion with serious artists since the early-20th century, he says, but ''the concept of beauty has migrated to popular art, and to design. We are surrounded by objects that want to be beautiful'' - he touches the salt cellar, my tape recorder, his own BlackBerry. By now he is wrestling with the lobster, another beautiful object, which has arrived lusciously bathed in butter. And it is time for another large whisky - just so that ''there is something to put in your menu list''.

But isn't the younger generation interested in ugliness in a different way, courting it with piercings and tattoos, deliberately flouting notions of beauty, I ask?

''Our notions of beauty, yes, but these are notions that change all the time. There should be a third book: On Charm. Charm is something else - it can depend on a glance, on the way you move a finger. So Barbra Streisand has a horrible nose but she has something else. There are other values: charm and sexiness.''

In Eco's extensive writings on politics and the television age, too, he recognises the power of charm: ''In the election of 2001, there was Berlusconi - who is a midget - but he has charm.'' My fish pie is long gone, but Eco finds that one of the noble crustacean's huge claws is putting up a fight: when I call a waiter to help out with a swift hammer blow, Eco waves the plate away - ''no, no, one should not work too hard to eat: that is slavery.''

He is more interested in returning to his theme. ''You know, I have written 40 books, but I am famous in Italy for a few sentences in one essay I wrote in 1961, on the quiz programme Buongiorno, where I demonstrate that in every civilisation people have wanted to worship superior beings - the Greek gods, the knights of the round table, superheroes. But television has realised that while the idol was once Greta Garbo, no one could be like Greta Garbo, now the model is the nice girl who looks like everyone else - no one has to feel inferior to her. And television also gives us the fall guy, over whom everybody can exercise his own sense of superiority. In this sense television has brought a radical change.''

Michael Grade has stopped listening by now - although this is very much his subject - because his guest has arrived: it is Harriet Harman, deputy leader of the Labour party. I toy with the idea of explaining their identities to Eco, but he is busy replying to a question of mine about whether he sees any rays of light in the dismal landscape of Italian politics. We discuss Walter Veltroni, the charismatic mayor of Rome (definitely a possessor of ''charm'', Eco says), but the well-known British faces next to us evoke no flicker of recognition in him: it is one of those moments when - despite television and globalised news - Europe seems very large, rather than increasingly small.

Eco has been well-placed to comment on the television age from its infancy: he worked on cultural programmes for Italy's RAI TV network as long ago as 1955. He migrated to publishing, as nonfiction editor at Casa Editrice Bompiani in Milan (where he stayed until 1975), while producing the early books that established him as an important commentator on medieval history and aesthetics. In 1959, too, he began writing a regular column for a monthly called Il Verri devoted to avant-garde linguistics and philosophy. From that point, his multiple careers - in academia, in journalism and after 1980's publication of The Name of the Rose in fiction - expanded in parallel. For decades he has written columns across the Italian press, most recently for the news weekly L'Espresso. Its title, ''La Bustina di Minerva'', sums up Eco's intellectual project. It means ''Minerva's matchbook'' (Minerva is a brand of matches as well as the goddess of the arts), thence the teasing idea that Eco the columnist scribbles his deep thoughts on the back of a book of matches. It is hard to know where intellectual inquiry turns into satire or just pure comedy (Eco once propounded a theory about computers, that Macs are Catholic while MS-DOS machines are Protestant, and actually it works very cleverly).

Many of the columns have been collected - the best-known are Misreadings and How to Travel with a Salmon - and there have been works of pure philosophy as well, such as Kant and the Platypus. Language and literary criticism makes up another impressive list of works, including Six Walks in the Fictional Woods, Experiences in Translation, and more than one work focusing on James Joyce.

It was in 1968 that he published his first book on pure semiotics, entitled The Absent Structure, which was revised and republished as A Theory of Semiotics in 1976. In 1971 he became the first professor of semiotics at the University of Bologna, a post he held until a few weeks ago.

''Yes,'' he tells me over his espresso, ''from'' - he looks at his watch - ''just a few days ago I have retired. I will keep my office, though - I have the first Oval Office, older than the one in the White House. It was part of a grand house that the university took over, it was an alcova - you know, for making love? - so it has secret entrances.''

Over our coffee, he takes out a cigarillo and puts it into his mouth. It is the last resort of the lifelong smoker, to suck it unlit - ''you get a little nicotine'' - and no one in the busy restaurant comments. ''Sometimes I am challenged in restaurants, and so I say, 'no, no, it is not tobacco; it is cocaine', and they say, 'oh, that's fine then''' - a huge belly laugh.

Whenever I bring up the idea of another novel, Eco makes a calm-down gesture with his hands, palms spread downwards. ''Each novel takes me six years, eight years in fact between The Rose and Foucault's Pendulum, and my last one [The Mysterious Flame of Queen Loana, 2004] was only a few years ago, so' '' He hardly wants to talk about another work of fiction - although he is eloquent on the subject of narrative, and its importance. So to shut me up on the subject, and because it is time to go, and because he is kind, Umberto Eco gives me a little present: the title of his next novel. Or perhaps it is just an ox.

Jan Dalley is the FT's arts editor.

J. Sheekey, London

1 x grilled lobster

1 x fish pie

1 x green beans

2 x large Macallan whisky

1 x glass Sauvignon blanc

1 x bottle of still mineral water

1 x espresso

1 x macciato

£108.06