I share the profound doubts of others that Pigou was a Soviet agent. Aside from anything else, Pigou was at Kings and not Trinity. If you are interested in a genuinely plausible fifth (sixth?) Cambridge spy, Wittgenstein who was at Trinity is a better bet. This is discussed in an extraordinarily fascinating book "The Jew of Linz" published by my fellow Australian, Kim Cornish. The title comes from a phrase in Mein Kampf in which Hitler traces his anti-Semitism to a "Jew of Linz" with whom he had gone to high school. Although the family had converted from Judaism, Wittgenstein had, in one of the most amazing coincidences in history, gone to the same high school at the same time as Hitler. The book then argues that Wittgenstein had been the person who had recruited Philby and the other Cambridge spies. This is from Kim's Wikipedia entry: 

"The Jew of Linz (1998) is a controversial book by Australian writer Kimberley Cornish. It alleges that the Austrian philosopher Ludwig Wittgenstein had a profound effect on Adolf Hitler when they were both pupils at the Realschule (high school) in Linz, Austria, in the early 1900s. He also alleges that Wittgenstein was involved in the Cambridge Five Soviet spy ring during the Second World War....

"Cornish also argues that Wittgenstein is the most likely suspect as recruiter of the 'Cambridge Five' spy ring. The author suggests that Wittgenstein was responsible for British decryption technology for the German Enigma code reaching the Red Army and that he thereby enabled the Red Army victories on the Eastern Front that liberated the camps and ultimately overthrew the Reich.

"He writes that the Soviet government offered Wittgenstein the chair in philosophy at what had been Lenin's university (Kazan) at a time (during the Great Purge) when ideological conformity was at a premium amongst Soviet academics and enforced by the very harshest penalties. Wittgenstein wanted to emigrate to Russia, first in the twenties, as he wrote in a letter to Paul Engelmann, and again in the thirties, either to work as a labourer or as a philosophy lecturer. Cornish argues that given the nature of the Soviet regime, the possibility that a non-Marxist philosopher (or even one over whom the government could exert no ideological control) would be offered such a post, is unlikely in the extreme." 


Dr Steven Kates
School of Economics, Finance
    and Marketing
RMIT University
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