These lines by the seventeenth-century poet George Herbert convey the role of imagination in research. They were used by Ian Donald to introduce his Victor Bonney lecture delivered to the Royal College of Surgeons of England on 31st October 1973, which is one of the many accounts given by him over the years describing the development of medical ultrasound. Its title is “Apologia”– not an expression of regret, but a spirited self-defence. (He added that he hoped its consequences would not be as lethal for the author as Socrates' “Apologia” was for him.)

Ian believed that accident and good luck had combined at the right time to open up for the medical profession a new diagnostic dimension. In the experiment, most of the worthwhile observations were unforeseen. A similar attitude was shown by Max Perutz, who won the Nobel Prize for his discovery of the structure of haemoglobin. “Creativity in science, as in the arts, cannot be organised. It arises spontaneously from individual talent. Well-run laboratories can foster it, but hierarchical organisation, inflexible, bureaucratic rules and mountains of futile paperwork can kill it. Discoveries cannot be planned; they pop up, like Puck, in unexpected corners.”

With the present bureaucratic ‘evidence based’ attitude to medicine, where multiple criteria have to be fulfilled before doing anything, it is doubtful whether Ian's experiment would have got off the ground, but he says he was driven inexorably onwards, so the bureaucrats would have a lot to battle with if he were alive today!