Mr Lévy, who in France goes simply by his initials BHL, has been doing the media rounds to promote his new work, On War in Philosophy.
In his book, which has received lavish praise from some quarters, the open-shirted Mr Lévy lays into the philosopher Immanuel Kant as being unhinged and a “fake”. To support his claims, he cites a certain Jean-Baptiste Botul, whom he describes as a post-War authority on Kant.
But the chorus of approval turned to laughter after a journalist from Le Nouvel Observateur pointed out that Mr Botul does not exist: he is a fictional character created in by a contemporary satirical journalist, Frédéric Pagès.
Alarm bells should have rung given that Mr Pagès, a journalist with Le Canard Enchaîneé, a satirical weekly, has penned one book under the Botul pseudonym entitled The Sex Life of Immanuel Kant.
He has even given rise to a school of philosophical thought called Botulism – a play on words with the lethal disease – and has created a theory of “La Metaphysique du Mou” the Metaphysics of the Flabby.
But Mr Lévy missed the joke, citing Mr Botul from a “series of lectures to the neo-Kantians of Paraguay” he supposedly gave after the war, in which he said that “their hero was an abstract fake, a pure spirit of pure appearance”.
Aude Lancelin, the Nouvel Obs journalist who spotted the blunder, said it was tantamount to “a nuclear gaffe that raises questions on the Lévy method”.
Mr Lévy took the humiliation on the chin last night in appearances in a series of evening TV shows. “I found the book astonishing,” he said, adding that Mr Pagès was a “very good philosopher.
“Hats off to the this invented but truer than real life Kant whose portrait, whether signed by Botul or Pagès still seems in line with my idea of (the philosopher),” he told the Libération.
Mr Pagès kept up the joke last night, saying: “It has never been firmly established that Botul didn’t exist and it cannot thus be ruled out that one day history will prove Bernard-Henri Lévy right.”