Teaching the principles of electromagnetism: quagmires and stepping-stones

It is acknowledged that electromagnetism is a very difficult subject, but reasons are given why its principles should be taught in all relevant degree and diploma courses. These reasons are based on the unifying influence of the principles and the help they give to professional engineers to change between specialisms during their careers. Maxwell´s advice on how to teach the subject is discussed and endorsed, particularly as regards the role of physical analogies which enable new concepts to be explored. Some of the difficulties arising in teaching the subject are discussed in a series of twelve questions and outline answers. The central role of energy distribution is stressed. The conclusion suggests that the principles of electromagnetism should be taught in the manner of a spiral staircase which revisits the same view at repeated higher levels. It is suggested that there should be courses in electromagnetism for professional engineers in mid-career. The importance of applications is mentioned