Jack Vaughan is a history teacher. He knows this because he has been told it by his best friend. He also knows that he is married. Again, he has been informed of this by his best friend.
Vaughan, as his best friend tells him he is known, is the protagonist of The Man Who Forgot His Wife, a new novel by John O'Farrell, author of the bestselling comic-political memoir Things Can Only Get Better.
Vaughan is quietly riding the Piccadilly Tube line, when he suddenly realises that he has no idea who he is, what his name is, or what he is doing in the outer reaches of West London. "I actually checked to see if there was a name tag on the inside of my jacket," Vaughan says. "It just said `Gap'."
Handily, he immediately fancies Maddy, his wife. Less handily, they are in the final stages of an acrimonious divorce. "We already have that in common," Vaughan pronounces optimistically, and starts waving flirtatiously at Maddy across the courtroom.
New Vaughan, in fact, is notably upbeat about everything in Old Vaughan's life. "So I'm a teacher!" he says. "Wow! That's not just a job, is it? That's a vocation!" Cue visions of his life as Dead Poets Society relocated to a South London comp.
This vision is not simply rose-tinted, it is luminous magenta: he is seeing the world through the filter of the handful of good memories that slowly return. Maddy, meanwhile, sees them through the filter of past rows.
This, roughly, is the Serious Theme of the novel: that there is no such thing as objective history or experience. There are only the stories we create for ourselves - the anecdotes we tell, reframing memories that are themselves selective and subjective. This is hammered home with all the subtlety of the blow to the head that Vaughan has suffered.
When he is not trying to be a Serious Author with Serious Themes, however, O'Farrell is very, very funny. Of his malfunctioning memory, for example, Vaughan says: "It was a shame my brain had no button just to switch it off and then switch it back on again."
(That said, not all the jokes work. A note to comic authors: comparing a marital row to Hitler's final solution is never a good idea. Ever.)
And unlike the everybloke narrators of similar novels (step up, any Nick Hornby protagonist), Vaughan is unquestionably a grown-up. He is not simply self-critical: his entire condition is essentially a heightened form of self-criticism. Forgetting his life allows him to see it through the eyes of others. This, he finds, is not always a welcome experience. But it does add a whole new dimension to Googling his own name.
The Man Who Forgot His Wife, Doubleday, hardback pound;14.99.