For many years, Operational Research, as the Brits call it, had no formal definition:
At a conference held in Dundee under the auspices of the British Association in 1947, the innovator of radar, Sir Robert Watson-Watt, stated that although he had been directly involved in the inauguration of operational research in the period to 1940, he had no recollection of any generally accepted definition emerging then or subsequently. The exception was his own ‘negative thesis,’ maintained with ‘damned iteration,’ that ‘Operational Research is not doing arithmetic for Air Staff.’