From the most senior of the positions that he held he took pleasure in debunking the pompous. He once told me how much he enjoyed the title of his army job, Army Deception: he thought it neatly described the majority of armies' daily work. As a director of the Army Camouflage School he invented a phantom army of inflatable tanks, aircraft and ships, all real enough to convince the German watchers that our resources were vaster than they were. That work alone warranted a knighthood, astonishingly not bestowed.
He was so good at explaining anything, particularly through the medium of exhibitions, that great corporations stood in line until James was ready. Philips, I was once told, had waited three years for him to start on their brilliant lighting exposition at Eindhoven. He almost totally designed the greatest innovation in ocean liners, the QE2 - like so many of the enterprises of the golden age of British design, now taken for granted but, as history shows, immensely influential in the whole sector of travel.
Through his extraordinary life he remained an unsung hero, yet he will continue to affect the millions of visitors to the 16 museums that he designed. He truly understood the importance of giving pleasure through design and the extraordinary entertainment that he created in the Battersea Pleasure Gardens has never been approached for public success.
In the 1950s, 1960s and 1970s his prodigious output gave example and enthusiasm to countless designers who were given these amazing demonstrations to follow: no one could, but all learnt immensely in the trying. He also leaves behind his book The ARTful Designer (1993) and this has to be required reading for anybody who can conceive that art should be a pleasure.