James Playfair (1738-1819) trained as a Church of Scotland minister at St Andrews University, and was appointed to Newtyle in Forfarshire in 1770. In 1777 he was translated to Meigle, and gained his DD from St Andrews in 1779. In 1800 he was appointed as principal of United College, and minister of St Leonard's church. While in St Andrews he produced a number of books on geography, including Geographical and Statistical Description of Scotland, published just before he died in 1819.
Lyon Playfair (1818-1898) was a noted chemist, working in Giessen, Germany with Europe's foremost chemist, von Liebig, was professor of chemistry at the Royal Institution in Manchester, chemist to the Geological Society, and was chosen to help Albert the prince consort with his scientific projects and to organise the Great Exhibition of 1851. He was appointed secretary for science and tried to set up science schools to prepare Britain to compete with technological advances in European manufacturing, but was unsuccessful in this venture. He carried on his research in many fields when appointed as professor of chemistry at Edinburgh University in 1858, and served on various royal commissions concerning scientific matters. Playfair entered Parliament in 1869 as the representative of St Andrews and Edinburgh Universities, speaking mainly on education; he was appointed as post-master general, having invented the postcard in 1870, and later deputy speaker. He was created Baron Playfair of St Andrews in 1892 and continued to speak on education, social welfare and health from the Lords. He recommended the foundation of a museum in South Kensington in honour of Queen Victoria's jubilee but did not live long enough to see the Victoria and Albert Museum open in 1899.