The extensive preface to the play points out that there is another dilemma: poor doctors are easily tempted to perform costly but useless (and in the best case harmless) operations or treatments on their patients for personal gain. "Could I not make a better use of a pocketful of guineas than this man is making of his leg?" This was reportedly inspired by the behaviour of a prominent Ear Nose and Throat specialist in London who had developed a simple and harmless operation to remove the uvula. This did not benefit any of his patients but made the surgeon a great deal of money.
Shaw credits Almroth Wright as the source of his information on medical science: "It will be evident to all experts that my play could not have been written but for the work done by Sir Alm[r]oth Wright on the theory and practice of securing immunization from bacterial diseases by the inoculation of vaccines made of their own bacteria."