"Churchill used to say that the Prof's brain was a beautiful piece of mechanism, and the Prof did not dissent from that judgement. He seemed to have a poor opinion of the intellect of everyone with the exception of Lord Birkenhead, Mr Churchill and Professor Lindemann; and he had a special contempt for the bureaucrat and all his ways. The Ministry of Supply and the Ordnance Board were two of his pet aversions, and he derived a great deal of pleasure from forestalling them with new inventions. In his appointment as Personal Assistant to the Prime Minister no field of activity was closed to him. He was as obstinate as a mule, and unwilling to admit that there was any problem under the sun which he was not qualified to solve. He would write a memorandum on high strategy one day, and a thesis on egg production on the next. He seemed to try to give the impression of wanting to quarrel with everybody, and of preferring everyone's room to their company; but once he had accepted a man as a friend, he never failed him, and there are many of his war-time colleagues who will ever remember him with deep personal affection. He hated Hitler and all his works, and his contribution to Hitler's downfall in all sorts of odd ways was considerable."