Despite his very specialised expertise, Cahn was an intellectual polymath of the old school who pushed hard for the integration of scientific and artistic skills. At Birmingham he organised a well received Art in Science exhibition, at Sussex he was on the governing committee of the Science Policy Research Unit, and he became external examiner for the Liberal Studies in Science course at the University of Manchester. A very widely read man, he was as able to hold forth on literature and art as on science. For example, he contributed a survey of the sociology of innovation. In 2004 "Journal of Materials Science" published a bibliography including 3 biographies, 10 topical articles, and 16 more philosophical, all relating to the history of materials science. Cahn was notable for his international range of contacts and the support he gave to the development of international links to promote the development of metallurgy and materials science in developing countries. From 1955 he contributed to the development of metallurgy in Argentina, and made repeated visits to the research centre Instituto de Fisica de Bariloche in the Andes. Later he developed close links with Indian metallurgy and materials science, through former researchers in his departments at Bangor and Sussex, and in his final years his contribution to Chinese metallurgy was recognised with honorary membership of the Chinese Academy of Sciences. He was elected a Fellow of the Royal Society of London in 1991. He was a foreign member of the Göttingen Academy of Sciences and Humanities, the Royal Spanish Academy of Sciences and the Indian National Science Academy. Cahn died of myelodysplasia induced leukaemia on 9 April 2007 in Cambridge. His four children include Sir Andrew Cahn and Alison Cahn, formerly a respected producer of television documentaries.