Dalkey Archive, 203 pp, $ 13.95, softcover.

If a book is any good, does it matter what you call it? The author insists this is a memoir; the publisher claims the work relentlessly blurs the line between fact and fiction. Me, I'm willing to believe just about anything, but don't be coy. Lie to me, just don't give the game away.

In Paris, back in the early '70s, for reasons that the author disingenuously claims not to understand, he was believed to be CIA. Mathews spent so much time denying the rumours that he became despondent, finally reasoning that the only way out was to act the part thrust upon him. There's the premise.

After a meeting of Oulipo, a literary group whose purpose is "to explore the potentialities mathematics might contribute to literature", Mathews was invited to lecture a group of dyslexics who were afraid to travel because schedules filled them with anxiety. His talk encouraged them to seek out departure times that could be read backwards and forwards, 01:10, for instance, or 15:51. Mathews's re- creation of this lecture, whether or not it occurred, is straight out of a Marx Brothers' movie and worth the price of admission. It also serves as his admission into some serious spy work, and things become interesting when foreign governments and extremist groups fall for his act. Both hilarity and fright ensue.

There are amazing coincidences in My Life in CIA that would succeed if the book was a comic caper-like when Mathews is hiding in a rolled-up carpet and is unwound in a fascist hangout and then rescued through the machinations of a sex-starved midget-but they don't because it isn't. Still, they're funny. Then suddenly Mathews goes into thriller mode, and his escape from France is almost worthy of the master of the genre, Charles McCarry.

Whatever the book is, its author is erudite and engaging. Too bad he demands we believe his story. I'm reminded of what Kenneth Rexroth's editor said to him when the poet submitted what purported to be his autobiography: "We have to call it a novel, Kenneth. No one's going to believe this shit."