Kimberley Cornish Century, £17.99

It is a spooky picture. The school photograph for the Linz Realschule in 1904-05 does indeed show a 14-year-old Adolf Hitler (identifiable without forelock or moustache) and, one down and two across, a younger-looking boy who appears to be Ludwig Wittgenstein. From the coincidence of two famous people at the same school at the same time, Kimberley Cornish constructs a Heath-Robinson contraption of eliding hypotheses - "could have been, should have been, must have been, was" - combining arrogance with misinformation.

His thesis is this. Hitler and Wittgenstein had adolescent dealings that determined both their careers. Wittgenstein was the Jew who inspired Hitler's lifelong anti-Semitism. Wittgenstein made him read Schopenhauer, from whom Hitler learned techniques of mass mind control. Wittgenstein, stricken with remorse, used other Schopenhauerish insights to convert and control the Cambridge spies, and thus bring Hitler down.

Everyone, no matter how eminent, who has ever written on either man has completely failed to spot what stares Cornish in the face- gosh! what a clever man Cornish thinks he is.

He hints that perhaps the imaginary...